50 (number)
Appearance
| ||||
---|---|---|---|---|
Cardinal | fifty | |||
Ordinal | 50th (fiftieth) | |||
Numeral system | quinquagesimal | |||
Factorization | 2 × 52 | |||
Divisors | 1, 2, 5, 10, 25, 50 | |||
Greek numeral | Ν´ | |||
Roman numeral | L | |||
Unicode symbol(s) | ↆ | |||
Binary | 1100102 | |||
Ternary | 12123 | |||
Senary | 1226 | |||
Octal | 628 | |||
Duodecimal | 4212 | |||
Hexadecimal | 3216 |
50 (fifty) is the natural number following 49 and preceding 51.
In mathematics
Fifty is the smallest number that is the sum of two non-zero square numbers in two distinct ways: 50 = 12 + 72 = 52 + 52.[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]
50 is a Stirling number of the first kind: and also a Narayana number:
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]
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Look up fifty in Wiktionary, the free dictionary.
In science
- The atomic number of tin
- The fifth magic number in nuclear physics
In religion
- In Kabbalah, there are 50 Gates of Wisdom (or Understanding) and 50 Gates of Impurity[citation needed]
- The traditional number of years in a jubilee period.[5]
- The Christian Feast of Pentecost takes place on the 50th day of the Easter Season
- The Jewish Pentecost takes place 50 days after the Passover feast (the holiday of Shavuoth).
In sports
- In cricket one day internationals, each side may bat for 50 overs.
In other fields
Fifty is:
- 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
- In years of marriage, the gold or "golden" wedding anniversary
- The speed limit, in kilometres per hour, of Australian and Canadian roads with unspecified limits.
See also
References
- ^ de Koninck, J.M. (2009). Those fascinating numbers. AMS Bookstore. p. 18. ISBN 0-8218-4807-0.
- ^ "Sloane's A005349 : Niven (or Harshad) numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-05-30.
- ^ "Sloane's A005277 : Nonients". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-05-30.
- ^ "Sloane's A005278 : Noncotients". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-05-30.
- ^ Leviticus 25:10
- ^ Karen Rhodes (1 February 1997). Booking Hawaii Five-O: An Episode Guide and Critical History of the 1968–1980 Television Detective Series. McFarland. p. 265. ISBN 978-0-7864-8666-3.