Fatto generale: 20 is the number of questions in the popular party game Twenty Questions.
Fatto matematico: 20 is the third composite number comprising the product of a squared prime and a prime, and also the second member of the (22)q family in this form.
Trivia: 20 is the number of baby teeth in the deciduous dentition.
Data storica: January 20th is the day in 1356 that Edward Balliol abdicates as King of Scotland.