Fatto generale: 21101 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 21101 is an unremarkable number.
Trivia: 21101 is a boring number.
Data storica: October 8th is the day in 1978 that Australia's Ken Warby sets the current world water speed record of 317.60mph at Blowering Dam, Australia.