Fatto generale: 90851 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 90851 is a boring number.
Trivia: 90851 is an unremarkable number.
Data storica: September 27th is the day in 1825 that the Stockton and Darlington Railway opens, and begins operation of the world's first service of locomotive-hauled passenger trains.