256678602017 has 2 divisors, whose sum is σ = 256678602018. Its totient is φ = 256678602016.

The previous prime is 256678602013. The next prime is 256678602029. The reversal of 256678602017 is 710206876652.

256678602017 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 159907213456 + 96771388561 = 399884^2 + 311081^2 .

It is a cyclic number.

It is not a de Polignac number, because 256678602017 - 2² = 256678602013 is a prime.

It is not a weakly prime, because it can be changed into another prime (256678602013) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128339301008 + 128339301009.

It is an arithmetic number, because the mean of its divisors is an integer number (128339301009).

Almost surely, 2^256678602017 is an apocalyptic number.

It is an amenable number.

256678602017 is a deficient number, since it is larger than the sum of its proper divisors (1).

256678602017 is an equidigital number, since it uses as much as digits as its factorization.

256678602017 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1693440, while the sum is 50.

The spelling of 256678602017 in words is "two hundred fifty-six billion, six hundred seventy-eight million, six hundred two thousand, seventeen".