This number is a prime.
It is alleged, yet unproven, that a monk was killed by a meteorite in Cremona, Italy, in 1511. In algebraic geometry, the problem of describing the Cremona group of spaces in three dimensions and higher has not been settled either. [Sullins]
The USS Arizona had a 1511-man crew during the attack on Pearl Harbor. [Hess]
"The School of Athens" by the Italian Renaissance artist Raphael was completed by 1511.