It is also the sum of the first six positive non-zero even numbers, , and a
Harshad number in
decimal, because the sum of its digits is six , which
evenly divides 42.[8]
the number of rooted ordered binary
trees with six leaves, and
the number of
noncrossing partitions of a set of five elements, as well as the ways in which five pairs of nested parentheses can be arranged, etc.
Additionally, 42 is the smallest number that is equal to the sum its non-prime
proper divisors; i.e. [10] (with the latter term representing the sixth
triangular number).[11]
42 is the number of
integer partition of
10: the number of ways of expressing 10 as a sum of positive integers.[14] 1111123, one of the forty-two unordered integer partitions of 10, has 42 ordered compositions, since
Where the
plane-vertex tiling 3.10.15 is constructible through elementary methods, the largest such tiling,
3.7.42, is not. This means that the 42-sided tetracontadigon is the largest such
regular polygon that can only tile a vertex alongside other regular polygons, without
tiling the plane.[18][19][20]
42 is the only known that is equal to the number of sets of four distinct positive integers — each less than — such that and are all multiples of . Whether there are other values remains an open question.[30]
42 is the resulting number of the original
Smith number: Both the sum of its digits, , and the sum of the digits in its prime factorization, , result in 42.[31]
42 is the fourth Robbins number, equivalently the number of alternating sign matrices.[34][35] It is also the number of ways to arrange the numbers through in a matrix such that the numbers in each row and column are in ascending order.
42 is the
magic constant of the smallest non-trivial
magic cube, a cube with entries of 1 through 27, where every row, column, corridor, and diagonal passing through the center sums to forty-two.[36][37]
42 is the smallest integer that can only be made from a minimal number of fours (seven) using only addition, subtraction, multiplication, and division, where an intermediate value has to be a non-integer:[citation needed]
In
decimal representation, the first three
digits of
pi, , can be arranged as a set of two
strings to yield:
42 is the
atomic mass of one of the naturally occurring stable isotopes of
calcium.
The angle rounded to whole degrees for which a
rainbow appears (the critical angle).
In 1966, mathematician Paul Cooper theorized that the fastest, most efficient way to travel across continents would be to bore a straight hollow tube directly through the
Earth, connecting a set of
antipodes, remove the air from the tube and fall through.[46] The first half of the journey consists of free-fall acceleration, while the second half consists of an exactly equal deceleration. The time for such a journey works out to be 42 minutes. Even if the tube does not pass through the exact center of the Earth, the time for a journey powered entirely by gravity (known as a
gravity train) always works out to be 42 minutes, so long as the tube remains friction-free, as while the force of gravity would be lessened, the distance traveled is reduced at an equal rate.[47][48] (The same idea was proposed, without calculation by
Lewis Carroll in 1893 in Sylvie and Bruno Concluded.[49]) Now we know that is inaccurate, and it only would take about 38 minutes.[50]
As determined by the Babylonians, in 79 years, Mars orbits the Sun almost exactly 42 times.[51]
The hypothetical efficiency of converting mass to energy, as per by having a given mass orbit a rotating black hole, is 42%, the highest efficiency yet known to modern physics.[52]
In Powers of Ten by Ray and Charles Eames, the known universe from large-scale to small-scale is represented by 42 different powers of ten. These powers range from 1025 meters to 10−17 meters.
In
TIFF (Tag Image File Format), the second
16-bitword of every file is 42, "an arbitrary but carefully chosen number that further identifies the file as a TIFF file".
In the military IRIG 106 Chapter 10[53] data recording standard, the hex value 0x464F52545974776F (ASCII "FORTYtwo") is used as a magic number to identify directory blocks.
In January 2004,
asteroid2001 DA42 was given the permanent name
25924 Douglasadams, for the author
Douglas Adams who popularized the number 42. Adams died in 2001.
Brian G. Marsden, the director of the
Minor Planet Center and the secretary for the naming committee, remarked that, with even his initials in the provisional designation, "This was sort of made for him, wasn't it?".
Kepler-42, a red dwarf in the constellation
Cygnus that hosts the three smallest
exoplanets found to date.
Ancient Egyptian religion: Over most of pharaonic Egyptian history, the empire was divided into 42
nomes. Ancient Egyptian religion and mythological structure frequently model this terrestrial structure.[56]
42 body parts of Osiris: In some traditions of the
Osiris myth,
Seth slays Osiris and distributes his 42 body parts all over Egypt. (In others, the number is fourteen and sixteen).[57]
42 negative confessions: In Ancient Egyptian religion, the 42 negative confessions were a list of questions asked of deceased persons making their journey through the underworld after death.
Ma'at was an abstract concept representing moral law, order, and truth in both the physical and moral spheres, as well as being an important goddess in the religion. In the judgment scene described in the Egyptian
Book of the Dead, which evolved from the
Coffin Texts and the
Pyramid Texts, 42 questions were asked of the deceased person as part of the assessment of Ma'at. If the deceased person could reasonably give answers to the 42 questions, they would be permitted to enter the afterlife. These 42 questions are known as the "42 Negative Confessions" and can be found in funerary texts such as the
Papyrus of Ani.
42 books in the core library: Clement of Alexandria states that the Egyptian temple library is divided into 42 "absolutely necessary" books that formed the stock of a core library. 36 contain the entire philosophy of the Egyptians which are memorized by the priests. While the remaining 6, are learned by the Pastophoroi (image-bearers).[58][59] (36 is like-wise a sacred number in Egyptian thought, related to time, in particular the thirty-six
Decan stars and the thirty-six, 10-day "weeks" in the
Egyptian year.[60]) The 42 books were not canonized like the Hebrew bible; they only supported and never replaced temple ritual. Hence, the destruction of the Egyptian temples and the cessation of the rituals ended Egyptian cultural continuity.[61]
In
Judaism, the number (in the Babylonian Talmud, compiled 375 AD to 499 AD) of the "Forty-Two Lettered Name" ascribed to God. Rab (or Rabhs), a 3rd-century source in the Talmud stated "The Forty-Two Lettered Name is entrusted only to him who is pious, meek, middle-aged, free from bad temper, sober, and not insistent on his rights". [Source: Talmud Kidduschin 71a, Translated by Rabbi I. Epstein].
Maimonides felt that the original Talmudic Forty-Two Lettered Name was perhaps composed of several combined divine names [Maimonides "Moreh"]. The apparently unpronouncable
Tetragrammaton provides the backdrop from the Twelve-Lettered Name and the Forty-Two Lettered Name of the Talmud.[citation needed]
In
Judaism, by some traditions the
Torah scroll is written with no fewer than 42 lines per column, based on the journeys of Israel.[62] In the present day, 42 lines is the most common standard,[63] but various traditions remain in use (see
Sefer Torah).
42 is the number with which God creates the Universe in
Kabbalistic tradition. In Kabbalah, the most significant name is that of the En Sof (also known as "
Ein Sof", "Infinite" or "Endless"), who is above the Sefirot (sometimes spelled "
Sephirot").[64] The Forty-Two-Lettered Name contains four combined names which are spelled in Hebrew letters (spelled in letters = 42 letters), which is the name of Azilut (or "
Atziluth" "Emanation"). While there are obvious links between the Forty-Two Lettered Name of the Babylonian Talmud and the Kabbalah's Forty-Two Lettered Name, they are probably not identical because of the Kabbalah's emphasis on numbers. The Kabbalah also contains a Forty-Five Lettered Name and a Seventy-Two Lettered Name.
The number 42 appears in various contexts in
Christianity. There are 42 generations (names) in the
Gospel of Matthew's version of the
Genealogy of Jesus; it is prophesied that for 42 months the
Beast will hold dominion over the Earth (
Revelation 13:5); 42 men of Beth-azmaveth were counted in the
census of men of
Israel upon return from exile (
Ezra 2:24);
God, because of a "curse"
Elisha put on them, sent/allowed bears to maul 42 teenage boys who mocked
Elisha for his baldness (
2 Kings 2:23-24), “For a thousand years in your sight are like a day that has just gone by, or like a watch in the night.” (
Psalm 90:4)→ “Fear God and give Him glory, because the hour of His judgment has come. Worship the One who made the heavens and the earth and the sea and the springs of waters.” (
Revelation 14:7)→ 1,000 years per day/24 hours per day ≈ 42 years/hour, etc.
The
Gutenberg Bible is also known as the "42-line Bible", as the book contained 42 lines per page.
In Japanese culture, the number 42 is considered unlucky because the numerals when pronounced separately—shi ni (four two)—sound like the word "
dying",[65] like the Latin word "
mori".
The fourth book in the series, the novel So Long, and Thanks for All the Fish, contains 42 chapters.
According to the novel Mostly Harmless, 42 is the street address of Stavromula Beta.
In 1994, Adams created the 42 Puzzle, a game based on the number 42. Adams says he
picked the number simply as a joke, with no deeper meaning.
Google also has a calculator
easter egg when one searches "the answer to the ultimate question of life, the universe, and everything." Once typed (all in lowercase), the calculator answers with the number 42.[67]
Alice's attempts at multiplication (chapter two of Alice in Wonderland) work if one uses base 18 to write the first answer, and increases the base by threes to 21, 24, etc. (the answers working up to 4 × 12 = "19" in base 39), but "breaks" precisely when one attempts the answer to 4 × 13 in base 42, leading Alice to declare "oh dear! I shall never get to twenty at that rate!"[citation needed]
Rule Forty-two in Alice's Adventures in Wonderland ("All persons more than a mile high to leave the court").
Rule 42 of the Code in the preface[70] to The Hunting of the Snark ("No one shall speak to the Man at the Helm").
In "fit the first" of The Hunting of the Snark the Baker had "forty-two boxes, all carefully packed, With his name painted clearly on each."[71]
The White Queen announces her age as "one hundred and one, five months and a day", which—if the best possible date is assumed for the action of Through the Looking-Glass (e.g., a date is chosen such that the rollover from February to March is excluded from what would otherwise be an imprecise measurement of "five months and a day")—gives a total of 37,044 days. If the Red Queen, as part of the same chess set, is regarded as the same age, their combined age is 74,088 days, or 42 × 42 × 42.[72]
"42" is a song from Mumford and Sons′ 2018 album Delta.
"42" is a song written and produced by hip-hop and record production trio
3Racha, which consists of members
Bang Chan,
Han Jisung, and
Seo Changbin of popular k-pop group
Stray Kids. A lyric in this song states, "Why do we live? What's the purpose? Is it 42? Stop speaking nonsense," which directly references The Hitchhiker's Guide to the Galaxy's definition of 42.
""42"" is a song from the 2018 album SR3MM by American rap duo
Rae Sremmurd.
"42" is a song from the 2019 album Don′t Panic by the progressive rock band
IZZ. The album is a partial concept album based on The Hitchhiker's Guide to the Galaxy.
"
42" is an episode of Doctor Who, set in
real time lasting approximately 42 minutes.
On the game show Jeopardy!, "
Watson" the IBM supercomputer has 42 "threads" in its avatar.[74]
42 is a film on the life of American baseball player Jackie Robinson.
Captain Harlock is sometimes seen wearing clothing with the number 42 on it.
In the Stargate Atlantis season 4 episode "Quarantine", Colonel Sheppard states that Dr. McKay's password ends in 42 because "It's the ultimate answer to the great question of life, the universe and everything."
In Star Wars: The Rise of Skywalker, the Festival of the Ancestors on Planet Pasaana is held every 42 years. The film itself was released in 2019, 42 years after the 1977 original Star Wars film. By a "whole string of pretty meaningless coincidences",[75] 2019 is the same year that 42 was found to be the largest possible natural number less than 100 to be expressed as a
sum of three cubes.[43]
In the TV show Lost, 42 is one of
the numbers used throughout the show for some of its mysteries.
There is a Belgian TV drama called Unit 42 about a special police unit that uses high-tech tools to go after criminals. One of the characters in the pilot episode explains that the unit was named based on the Hitchhiker's Guide To The Galaxy.
Squadron 42 is a video game set in the Star Citizen Universe with an unspecified release date.
Sports
The
jersey number of
Jackie Robinson, which is the only number
retired by all
Major League Baseball teams. Although the number was retired in 1997,
Mariano Rivera of the
New York Yankees, the last professional baseball player to wear number 42, continued to wear it until he retired at the end of the 2013 season. As of the 2014 season, no player ever again wore the number 42 in Major League Baseball except on
Jackie Robinson Day (April 15), when all uniformed personnel (players, managers, coaches, and umpires) wear the number.
The architects of the
Rockefeller Center in
New York City worked daily in the
Graybar Building where on "the twenty-fifth floor, one enormous drafting room contained forty-two identical drawing boards, each the size of a six-seat dining room table; another room harboured twelve more, and an additional fourteen stood just outside the principals' offices at the top of the circular iron staircase connecting 25 to 26".[77]
In the
Rockefeller Center (
New York City) there are a total of "forty-two elevators in five separate banks"[78] which carry tenants and visitors to the sixty-six floors.
Comics
Miles Morales was bitten by a spider bearing the number 42, causing him to become a Spider-Man. The number was later heavily referenced in the film Spider-Man: Into the Spider-Verse. The use of 42 within the franchise references Jackie Robinson's use of the number, though many fans incorrectly believed it to be a Hitchhiker's Guide to the Galaxy reference.[79]
Other fields
+42 is the historical Select Country for the former country of
Czechoslovakia.
42 in Chinese reads sì èr, which is very close to shì a (是啊), which means 'yes'. It was once popular among young Chinese to send '42' as a short message to stand for 'yes'.[citation needed]
42 is the sum of the numbers on a pair of dice.
42 (dominoes) is a trick-taking game played with dominoes, rather than cards. Originated and predominantly found in Texas.
42 is the number of times a standard sheet of paper would need to be folded over onto itself for the thickness of the folded piece of paper to be thick enough to reach the
Moon from the surface of the
Earth.[82]
^The eleventh triangular number is
66 (and sixth
hexagonal number),[11][23] that is also the third sphenic number, following 42 and 30.[6] These first three sphenic numbers are also consecutive (fifth, sixth, and seventh) members in Lemming's simulation sequence, where opposing triangles (starting with just one) are successively joined at vertices (without overlaps in the interior); in this sequence, values represent the total number of triangles joined at each generational step.[24][25] The sum of these three terms 30 + 42 + 66 =
138, which is the ninth term. Where 42 is the twenty-eighth
composite number,[26] the number of
integer partitions of the twenty-eighth28-gonal pyramidal number into distinct 28-gonal pyramidal numbers is 42.[27]
^The sequence of minimum diagonals by such -faced polyhedra follows the sequence of pronic numbers, whose
indexes start with 4 (for a square), rather than 0.[29][1]
"(Quoting from Scott Glazer): Trying to come up with a significant number to search for, I thought of 42 (the answer to life, the universe, and everything in Hitchhikers's Guide to the Galaxy.) 42 would be way too common of course, so I went for 424242. Came back that this shows up at position 242423. Add one (for the decimal point, I lamely rationalize here) and you get 242424, the reverse of the original input. Now that's meaningful... or something.
"[Editors Note] Amusingly enough, the entire string returned is 242424242. If you disregard either of the ending twos, you find that it's the same position at which you find 42424242. Ahh, the
palindromic possibilities inherent in a reversible meaning of life string."
^Carroll, Lewis (29 December 1893). "Chapter 7".
Sylvie and Bruno Concluded. Vol. 2. illustrated by
Harry Furniss. United Kingdom: Macmillan and Co. Each railway is in a long tunnel, perfectly straight: so of course the middle of it is nearer the centre of the globe than the two ends: so every train runs half-way down-hill, and that gives it force enough to run the other half up-hill.
^Berard (April 2009).
"IRIG 106 Telemetry Standard Chapter 10"(PDF). U.S. Army White Sands Missile Range, New Mexico: Range Commanders Council.
Archived(PDF) from the original on 2020-11-12. Retrieved 2010-11-10.
^Assman, Jan (2008). Of God and Gods: Egypt, Israel, and the Rise of Monotheism (George L. Mosse Series in Modern European Cultural and Intellectual History) (Kindle ed.). The University of Wisconsin Press. p. Kindle Location 195.
ISBN978-0299225544.
^Assman, Jan (2008). Of God and Gods: Egypt, Israel, and the Rise of Monotheism (George L. Mosse Series in Modern European Cultural and Intellectual History) (Kindle ed.). The University of Wisconsin Press. p. Kindle Location 576.
ISBN978-0299225544.
^Assman, Jan (2008). Of God and Gods: Egypt, Israel, and the Rise of Monotheism (George L. Mosse Series in Modern European Cultural and Intellectual History) (Kindle ed.). The University of Wisconsin Press. p. Kindle Location 1364.
ISBN978-0299225544.
^Clement of Alexandria (1885).
"Book VI:IV". In Roberts, Alexander; James, Sir; Coxe, Arthur (eds.). The Stromata, or Miscellanies (With Active Table of Contents) (Kindle ed.). p. Kindle Location 11498.
^Assman, Jan (2008). Of God and Gods: Egypt, Israel, and the Rise of Monotheism (George L. Mosse Series in Modern European Cultural and Intellectual History) (Kindle ed.). The University of Wisconsin Press. p. Kindle Location 1380.
ISBN978-0299225544.
^Assman, Jan (2008). Of God and Gods: Egypt, Israel, and the Rise of Monotheism (George L. Mosse Series in Modern European Cultural and Intellectual History) (Kindle ed.). The University of Wisconsin Press. p. Kindle Location 1418.
ISBN978-0299225544.
^Ganzfried, R. Solomon (1902).
קסת הסופר [Keset haSofer] (in Hebrew and English). Translated by Friendman, Jen (First ed.). Bardejov: דפוס יוסף מאיר בלייער. It is the custom to have no fewer than 48 lines, representing the journeys of Israel, and some say no fewer than 42, because of what God did in the Sinai wilderness at Kadesh. Also, we don't have more than 60 lines, representing the 60 myriads of Israel who received the Torah.
^Jacobs, Joseph; Eisenstein, Judah; Executive Committee of the Editorial Board; Blau, Ludwig (1906).
"Scroll of the Law (Hebrew, "Sefer Torah")". Jewish Encyclopedia. Retrieved 12 February 2020. (At the present day the forty-two-lined column is the generally accepted style of the scroll, its length being about 24 inches.)