256605706013 has 2 divisors, whose sum is σ = 256605706014. Its totient is φ = 256605706012.

The previous prime is 256605705991. The next prime is 256605706043. The reversal of 256605706013 is 310607506652.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 253730816089 + 2874889924 = 503717^2 + 53618^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-256605706013 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256605706043) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128302853006 + 128302853007.

It is an arithmetic number, because the mean of its divisors is an integer number (128302853007).

Almost surely, 2^256605706013 is an apocalyptic number.

It is an amenable number.

256605706013 is a deficient number, since it is larger than the sum of its proper divisors (1).

256605706013 is an equidigital number, since it uses as much as digits as its factorization.

256605706013 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 226800, while the sum is 41.

The spelling of 256605706013 in words is "two hundred fifty-six billion, six hundred five million, seven hundred six thousand, thirteen".