Fait mathématique: 21460 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Culture générale: 21460 is an unremarkable number.
Date historique: October 2nd is the day in 1928 that the "Prelature of the Holy Cross and the Work of God", commonly known as Opus Dei, is founded by Saint Josemaría Escrivá.