Fatto generale: 172 is the record in miles per hour of John White's shot in squash.
Fatto matematico: 172 is the sum of Euler's totient function φ(x) over the first twenty-three integers.
Trivia: 172 is the record in miles per hour of John White's shot in squash.
Data storica: June 20th is the day in 1956 that a Venezuelan Super-Constellation crashes in the Atlantic Ocean off Asbury Park, New Jersey, killing 74 people.