Fatto generale: 1575 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 1575 is the number of partitions of 24.
Trivia: 1575 is a boring number.
Data storica: April 23rd is the day in 215 BC that a temple is built on the Capitoline Hill dedicated to Venus Erycina to commemorate the Roman defeat at Lake Trasimene.