Fatto generale: 813 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 813 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Trivia: 813 is a boring number.
Data storica: March 23rd is the day in 2001 that the Russian Mir space station is disposed of, breaking up in the atmosphere before falling into the southern Pacific Ocean near Fiji.