256762807813 has 4 divisors (see below), whose sum is σ = 256778239180. Its totient is φ = 256747376448.

The previous prime is 256762807783. The next prime is 256762807817. The reversal of 256762807813 is 318708267652.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 200164970404 + 56597837409 = 447398^2 + 237903^2 .

It is a cyclic number.

It is not a de Polignac number, because 256762807813 - 2¹⁷ = 256762676741 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256762807817) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7690698 + ... + 7724011.

It is an arithmetic number, because the mean of its divisors is an integer number (64194559795).

Almost surely, 2^256762807813 is an apocalyptic number.

It is an amenable number.

256762807813 is a deficient number, since it is larger than the sum of its proper divisors (15431367).

256762807813 is a wasteful number, since it uses less digits than its factorization.

256762807813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15431366.

The product of its (nonzero) digits is 6773760, while the sum is 55.

The spelling of 256762807813 in words is "two hundred fifty-six billion, seven hundred sixty-two million, eight hundred seven thousand, eight hundred thirteen".