977

977 is a prime number. It is a Stern prime.

977 has a representation as a sum of two squares: 977 = 4² + 31².

977 is the hypotenuse of a primitive Pythagorean triple: 977² = 248² + 945².

977 is the first prime that results in a cube if added to the sum of its digits: 977 + 9 + 7 + 7 = 1000.

In the 1950 movie Harvey, Dr. Sanderson prescribes "Formula 977" to Elwood P. Dowd (James Stewart).

Source: Prime Curios!