Fatto generale: 8520 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 8520 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Trivia: 8520 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Data storica: April 29th is the day in 2004 that Dick Cheney and George W. Bush testify before the 9/11 Commission in a closed, unrecorded hearing in the Oval Office.