Hecho general: 9811 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Hecho matemático: 9811 is an unremarkable number.
Trivia: 9811 is a boring number.
Fecha histórica: November 10th is the day in 1847 that the passenger ship Stephen Whitney is wrecked in thick fog off the southern coast of Ireland, killing 92 of the 110 on board.