269

269 is a prime number.

269 has a representation as a sum of two squares: 269 = 10² + 13².

269 and 271 form a twin prime pair.

269 is the hypotenuse of a primitive Pythagorean triple: 269² = 69² + 260².

The 269th day of a non-leap year is 26 September (26/9).

Source: Prime Curios!