Fait général: 21066 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fait mathématique: 21066 is an unremarkable number.
Culture générale: 21066 is a boring number.
Date historique: September 3rd is the day in 1914 that William, Prince of Albania leaves the country after just six months due to opposition to his rule.