256816944656 has 20 divisors (see below), whose sum is σ = 497772756204. Its totient is φ = 128359459200.

The previous prime is 256816944647. The next prime is 256816944733. The reversal of 256816944656 is 656449618652.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 79289549056 + 177527395600 = 281584^2 + 421340^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3020075 + ... + 3103946.

Almost surely, 2^256816944656 is an apocalyptic number.

It is an amenable number.

256816944656 is a deficient number, since it is larger than the sum of its proper divisors (240955811548).

256816944656 is a wasteful number, since it uses less digits than its factorization.

256816944656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6126650 (or 6126644 counting only the distinct ones).

The product of its digits is 74649600, while the sum is 62.

The spelling of 256816944656 in words is "two hundred fifty-six billion, eight hundred sixteen million, nine hundred forty-four thousand, six hundred fifty-six".