Fatto generale: 52500 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 52500 is a boring number.
Trivia: 52500 is an unremarkable number.
Data storica: September 27th is the day in 1590 that Pope Urban VII dies 13 days after being chosen as the Pope, making his reign the shortest papacy in history.