Fatto matematico: 6506 is a value of n for which the first n binary digits of p form a prime.
Trivia: 6506 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Data storica: October 23rd is the day in 1946 that the United Nations General Assembly convenes for the first time, at an auditorium in Flushing, Queens, New York City.