Fatto generale: 23506 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 23506 is an uninteresting number.
Trivia: 23506 is a boring number.
Data storica: May 9th is the day in 1904 that the steam locomotive City of Truro becomes the first steam engine in Europe to exceed 100 mph (160 km/h).