256564857545 has 16 divisors (see below), whose sum is σ = 326949920640. Its totient is φ = 192728358144.

The previous prime is 256564857529. The next prime is 256564857547. The reversal of 256564857545 is 545758465652.

It is a cyclic number.

It is not a de Polignac number, because 256564857545 - 2⁴ = 256564857529 is a prime.

It is a super-2 number, since 2×256564857545² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (256564857547) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11939189 + ... + 11960658.

It is an arithmetic number, because the mean of its divisors is an integer number (20434370040).

Almost surely, 2^256564857545 is an apocalyptic number.

It is an amenable number.

256564857545 is a deficient number, since it is larger than the sum of its proper divisors (70385063095).

256564857545 is a wasteful number, since it uses less digits than its factorization.

256564857545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23899984.

The product of its digits is 201600000, while the sum is 62.

The spelling of 256564857545 in words is "two hundred fifty-six billion, five hundred sixty-four million, eight hundred fifty-seven thousand, five hundred forty-five".