256907625137857 has 4 divisors (see below), whose sum is σ = 256962957390000. Its totient is φ = 256852292885716.

The previous prime is 256907625137809. The next prime is 256907625137861. The reversal of 256907625137857 is 758731526709652.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 256907625137857 - 2¹¹ = 256907625135809 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 256907625137857.

It is not an unprimeable number, because it can be changed into a prime (256907625137057) 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, 27666119107 + ... + 27666128392.

It is an arithmetic number, because the mean of its divisors is an integer number (64240739347500).

Almost surely, 2^{256907625137857} is an apocalyptic number.

It is an amenable number.

256907625137857 is a deficient number, since it is larger than the sum of its proper divisors (55332252143).

256907625137857 is an equidigital number, since it uses as much as digits as its factorization.

256907625137857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55332252142.

The product of its (nonzero) digits is 1333584000, while the sum is 73.

The spelling of 256907625137857 in words is "two hundred fifty-six trillion, nine hundred seven billion, six hundred twenty-five million, one hundred thirty-seven thousand, eight hundred fifty-seven".