Fifty is the smallest number that is the sum of two non-zero
square numbers in two distinct ways: 50 = 12 + 72 = 52 + 52 (see image).[1] It is also the sum of three squares, 50 = 32 + 42 + 52, and the sum of four squares, 50 = 62 + 32 + 22 + 12. It is a
Harshad number.[2]
There is no solution to the equation
φ(x) = 50, making 50 a
nontotient.[3] Nor is there a solution to the equation x − φ(x) = 50, making 50 a
noncototient.[4]
Fifty is the sum of the number of faces that make up the
Platonic solids (4 + 6 + 8 + 12 + 20 = 50).
In Hindu
tantric tradition, the number 50 holds significance as the 50
Rudras in the
Malinīvijayottara correlate with the 50
phonemes of
Sanskrit, as well as with the 50 severed heads worn around goddess
Kali's head. The
mantraAham ("I am"), as laid out in the
Vijñāna Bhairava represents the first अ(a) and last ह(ha) phonemes of the Sanskrit alphabet and is believed to represent
ultimate reality, in accordance with its
non-dual philosophy.
There are 50 states in the United States of America.
The TV show Hawaii Five-O and its reimagined version, Hawaii Five-0, are so called because
Hawaii is the last (50th) of the states to officially become a state.
5-O (Five-Oh) -
Slang for police officers and/or a warning that police are approaching. Derived from the television show Hawaii Five-O[6]
A calibre of ammunition (0.50 inches: see
.50 BMG)
In millimetres, the
focal length of the normal lens in 35 mm photography
The
percentage (50%) equivalent to one half, so that the phrase "fifty-fifty" commonly expresses something divided equally in two; in business this is often denoted as being the ultimate in equal partnership
Fifty (outlet store) - Formerly "Fifty Outlet". Outlet stores, mostly in Spain, owned by Tendam, selling its brands e.g. Cortefiel, Springfield, and others'