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 coined the name Fibonax for this number.
André Joyce has given the name "rootbeer" for this number.