697381

Properties

Appears in sequences

• Primes p such that sigma(2p-1) is a prime q.at n=12A247789
• Numbers k such that sigma(2*k-1) is a prime p.at n=33A247820
• Upper twin primes which correspond to the hypotenuse in a Pythagorean triple whose short leg is also a prime.at n=18A284035
• Hypotenuses of primitive Pythagorean triangles two sides of which are Pythagorean primes.at n=18A308341
• Prime numbersat n=56360