Fatto generale: 21739 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 21739 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Trivia: 21739 is an unremarkable number.
Data storica: July 8th is the day in 1896 that William Jennings Bryan delivers his Cross of Gold speech advocating bimetalism at the 1896 Democratic National Convention in Chicago.