51 may refer to:
*
51 (number)
51 (fifty-one) is the natural number following 50 and preceding 52.
In mathematics
Fifty-one is
* a pentagonal number as well as a centered pentagonal number and an 18-gonal number
*the 6th Motzkin number, telling the number of ways to dra ...
* The year
**
51 BC
**
AD 51
**
1951
Events
January
* January 4 – Korean War: Third Battle of Seoul – Chinese and North Korean forces capture Seoul for the second time (having lost the Second Battle of Seoul in September 1950).
* January 9 – The Government of the Uni ...
**
2051
*
''51'' (film), a 2011 American horror film directed by Jason Connery
* "
Fifty-One", an episode of the American television drama series ''Breaking Bad''
*
''51'' (album), a 2012 mixtape by rapper Kool A.D.
* "Fifty One", a song by Karma to Burn from the album ''
V'', 2011
*
51 Nemausa, a main-belt asteroid
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