Fatto generale: 20753 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 20753 is an unremarkable number.
Trivia: 20753 is an uninteresting number.
Data storica: October 25th is the day in 1924 that the forged Zinoviev Letter is published in the Daily Mail, wrecking the British Labour Party's hopes of re-election.