Fatto matematico: 21180 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Trivia: 21180 is an uninteresting number.
Data storica: December 26th is the day in 2003 that a magnitude 6.6 earthquake devastates southeast Iranian city of Bam, killing tens of thousands and destroying the citadel of Arg-é Bam.