Fait général: 21551 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fait mathématique: 21551 is an uninteresting number.
Culture générale: 21551 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Date historique: January 1st is the day in 414 that Galla Placidia, half-sister of Emperor Honorius, is married to the Visigothic king Ataulf at Narbonne.