Googology Wiki
Googology Wiki

50 (fifty) is a positive integer following 49 and preceding 51. Its ordinal form is written "fiftieth" or 50th.


  • 50 is an even composite number.
  • 50 is the number of known Mersenne primes and perfect numbers.
  • Szekeres snark has 50 bertices.[1]
  • 50 is the number of US states.

In googology

In Greek-based number-naming systems, 50 is associated with prefix "pentaconta-", and with prefix "quinquaginti-" in Latin systems.

Currency-related use

It is also the prize for correctly answering the first question in the German game show Wer wird Millionär? in euros.

In chess

There is a fifty-move rule preventing endless chess games.


  1. MathWorld, Szekeres Snark