Fait mathématique: 20575 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Culture générale: 20575 is an uninteresting number.
Date historique: April 30th is the day in 1937 that the Philippines holds a plebiscite for Filipino women on whether they should be extended the right to suffrage; over 90% would vote in the affirmative.