9661

9661 is a prime number.

9661 is the lower prime of a difference of 16 between consecutive primes (A031934).

9661 has a representation as a sum of two squares; it is the sum of two consecutive squares (A027862 and A163251): 9661 = 69² + 70².

9661 is the hypotenuse of a primitive Pythagorean triple (A067756 and A140391): 9661² = 139² + 9660².

9661 is a divisor of 26¹⁵ - 1.

Source: On-Line Encyclopedia of Integer Sequences