Fatto generale: 91878 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 91878 is an unremarkable number.
Trivia: 91878 is a boring number.
Data storica: July 21st is the day in 1545 that the first landing of French troops on the coast of the Isle of Wight during the French invasion of the Isle of Wight.