General fact: 21273 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Mathematical fact: 21273 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Trivia: 21273 is an uninteresting number.
Historical date: March 29th is the day in 1999 that a magnitude 6.8 earthquake strikes the Chamoli district in the Indian state of Uttar Pradesh, killing 103.