Fatto matematico: 2616 is the number of graphs with 9 vertices and 6 cycles.
Trivia: 2616 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Data storica: February 28th is the day in 1942 that the heavy cruiser USS Houston is sunk in the Battle of Sunda Strait with 693 crew members killed, along with HMAS Perth which lost 375 men.