Fait général: 21191 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fait mathématique: 21191 is a boring number.
Culture générale: 21191 is a boring number.
Date historique: January 6th is the day in 1839 that the most damaging storm in 300 years sweeps across Ireland, damaging or destroying more than 20% of the houses in Dublin.