67 is the natural number following 66 and preceding 68.
In mathematics
Sixty-seven is the 19th prime number (the next is 71), an irregular prime, a lucky prime, and the sum of five consecutive primes (7 + 11 + 13 + 17 + 19).
It is a discriminant to the Heegner number -67.
In astronomy
Other fields
Sixty-seven is also: