97

97 is the largest two-digit prime number.

97 is the smallest prime that is the sum of a prime number of consecutive primes as well as the sum of a composite number of consecutive composite numbers: 97 = 29 + 31 + 37 = 22 + 24 + 25 + 26.

The first four pairs of digits following the decimal point of 1/97 are powers of three: 1/97 = 0.01030927. . . .

97 has a representation as a sum of two squares: 97 = 4² + 9².


The Gregorian calendar has 97 leap days every 400 years.

Source: Prime Curios!