Fatto matematico: 4503 is the largest number that is not the sum of 4 or fewer squares of composites.
Trivia: 4503 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 1986 that a fire at the Central library of the City of Los Angeles Public Library damages or destroys 400,000 books and other items.