Fatto generale: 21065 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 21065 is an unremarkable number.
Trivia: 21065 is an uninteresting number.
Data storica: September 2nd is the day in 1957 that President Ngo Dinh Diem of South Vietnam becomes the first foreign head of state to make a state visit to Australia.