Hecho matemático: 9396 is the number of symmetric 3×3 matrices in base 6 with determinant 0.
Trivia: 9396 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fecha histórica: September 21st is the day in 1435 that an agreement between Charles VII of France and Philip the Good ends the partnership between the English and Burgundy in Hundred Years' War.