Fait général: 21712 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fait mathématique: 21712 is an unremarkable number.
Culture générale: 21712 is an uninteresting number.
Date historique: June 11th is the day in 1998 that Compaq Computer pays $9 billion for Digital Equipment Corporation in the largest high-tech acquisition.