Fatto generale: 21474 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 21474 is an unremarkable number.
Trivia: 21474 is an uninteresting number.
Data storica: October 16th is the day in 1906 that the Captain of Köpenick fools the city hall of Köpenick and several soldiers by impersonating a Prussian officer.