55 (fifty-five) is a positive integer following 54 and preceding 56. Its ordinal form is written "fifty-fifth" or 55th.
55 is an odd composite number.
55 is the 10th triangular number, and therefore the number of tiles in a double-nine domino set.
55 is a repdigit number.
55 is the 10th Fibonacci number.
In googology Edit
In Greek-based number-naming systems, 55 is associated with prefix "pentapentaconta-", and with prefix "quinquinquaginti-" in Latin systems.
SuperJedi224 calls this number Fibonax.
See also Edit
- ↑ Naming Large Fibonacci Numbers