256975816 has 8 divisors (see below), whose sum is σ = 481829670. Its totient is φ = 128487904.

The previous prime is 256975813. The next prime is 256975843. The reversal of 256975816 is 618579652.

It can be written as a sum of positive squares in only one way, i.e., 236236900 + 20738916 = 15370^2 + 4554^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a self number, because there is not a number n which added to its sum of digits gives 256975816.

It is not an unprimeable number, because it can be changed into a prime (256975813) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16060981 + ... + 16060996.

Almost surely, 2^256975816 is an apocalyptic number.

It is an amenable number.

256975816 is a deficient number, since it is larger than the sum of its proper divisors (224853854).

256975816 is a wasteful number, since it uses less digits than its factorization.

256975816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32121983 (or 32121979 counting only the distinct ones).

The product of its digits is 907200, while the sum is 49.

The square root of 256975816 is about 16030.4652458998. The cubic root of 256975816 is about 635.7661746092.

It can be divided in two parts, 25697 and 5816, that added together give a palindrome (31513).

The spelling of 256975816 in words is "two hundred fifty-six million, nine hundred seventy-five thousand, eight hundred sixteen".