math_fact: 1137 is the maximum value of n so that there exist 7 denominations of stamps so that every postage from 1 to n can be paid for with at most 7 stamps.
trivia: 1137 is an uninteresting number.
historical_date: February 10th is the day in 1258 that Baghdad falls to the Mongols, and the Abbasid Caliphate is destroyed.