Hecho general: 6445 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Hecho matemático: 6445 is a boring number.
Trivia: 6445 is a boring number.
Fecha histórica: August 23rd is the day in 1514 that Battle of Chaldiran ended with a decisive victory for the Sultan Selim I, Ottoman Empire, over the Shah Ismail I, Safavids founder.