Fait mathématique: 17039 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Culture générale: 17039 is an uninteresting number.
Date historique: August 25th is the day in 1875 that Captain Matthew Webb became the first person to swim across the English Channel, traveling from Dover, England, to Calais, France, in 22 hours.