Hecho general: 7573 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Hecho matemático: 7573 is a boring number.
Trivia: 7573 is an unremarkable number.
Fecha histórica: September 24th is the day in 1645 that Battle of Rowton Heath, Parliamentarian victory over a Royalist army commanded in person by King Charles.