Fatto generale: 81481 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 81481 is a boring number.
Trivia: 81481 is an unremarkable number.
Data storica: February 1st is the day in 1876 that a murder conviction effectively forces the violent Pennsylvanian Irish anti-owner coal miners, the "Molly Maguires", to disband.