Fatto generale: 16 is the number of teams that qualified for the finals of the FIFA World Cup from 1934 through 1978 (although for various reasons, only 15 competed in the 1938 and 1950 finals).
Fatto matematico: 16 is the only integer that equals mn and nm, for some unequal integers m and n (m = 4, n = 2, or vice versa).
Trivia: 16 is the number of personality types in the Myers-Briggs classification system.
Data storica: January 16th is the day in 929 that Emir Abd-ar-Rahman III established the Caliphate of Córdoba.