Hecho general: 9233 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Hecho matemático: 9233 is the number of different arrangements (up to rotation and reflection) of 13 non-attacking queens on a 13×13 chessboard.
Trivia: 9233 is an uninteresting number.
Fecha histórica: April 11th is the day in 1981 that a massive riot in Brixton, South London, results in almost 300 police injuries and 65 serious civilian injuries.