71821

Properties

Appears in sequences

• Numbers having exactly four anti-divisors.at n=29A066469
• Prime hypotenuses of Pythagorean triangles with a prime leg.at n=16A067756
• Primes of the form (4*k + 1)^2 + (4*k + 2)^2 where k=0,1,2,3,...at n=15A087871
• Primes of the form (p^k + k - 1)/k for prime p and some k > 1.at n=23A230444
• Greatest prime factor of n^7+1.at n=30A240550
• Primes that can be generated by the concatenation in base 8, in ascending order, of two consecutive integers read in base 10.at n=26A287310
• Primes of the form (p^k+1)/2 where p is prime and k > 1.at n=22A308442
• Value of prime number D for incrementally largest values of minimal x satisfying the equation x^2 - D*y^2 = -3.at n=29A336801
• Value of prime number D for incrementally largest values of minimal y satisfying the equation x^2 - D*y^2 = -3.at n=26A341077
• Numbers k such that d(k) < d(k+1) < d(k+2) < d(k+3) < d(k+4), where d(n) is the number of divisors of n.at n=14A364717
• Prime numbersat n=7108