General fact: 16573 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Mathematical fact: 16573 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Trivia: 16573 is a boring number.
Historical date: May 16th is the day in 1843 that the first major wagon train heading for the Pacific Northwest sets out on the Oregon Trail with one thousand pioneers from Elm Grove, Missouri.