Fatto matematico: 58509 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Trivia: 58509 is an uninteresting number.
Data storica: March 10th is the day in 1891 that Almon Strowger, an undertaker in Topeka, Kansas, patents the Strowger switch, a device which led to the automation of telephone circuit switching.