Fatto matematico: 8515 is a value of n for which n, 2n, 3n, and 4n all use the same number of digits in Roman numerals.
Trivia: 8515 is a boring number.
Data storica: April 24th is the day in 1932 that Benny Rothman leads the mass trespass of Kinder Scout, leading to substantial legal reforms in the United Kingdom.