Fait mathématique: 2309 is the largest prime factor of 2 × 3 × 5 × 7 × 11 - 1.
Culture générale: 2309 is an uninteresting number.
Date historique: April 27th is the day in 1578 that Duel of the Mignons claims the lives of two favourites of Henry III of France and two favorites of Henry I, Duke of Guise.