256669957 has 2 divisors, whose sum is σ = 256669958. Its totient is φ = 256669956.

The previous prime is 256669939. The next prime is 256669979. The reversal of 256669957 is 759966652.

256669957 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 239909121 + 16760836 = 15489^2 + 4094^2 .

It is a cyclic number.

It is not a de Polignac number, because 256669957 - 2²³ = 248281349 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 256669898 and 256669907.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256661957) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128334978 + 128334979.

It is an arithmetic number, because the mean of its divisors is an integer number (128334979).

Almost surely, 2^256669957 is an apocalyptic number.

It is an amenable number.

256669957 is a deficient number, since it is larger than the sum of its proper divisors (1).

256669957 is an equidigital number, since it uses as much as digits as its factorization.

256669957 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6123600, while the sum is 55.

The square root of 256669957 is about 16020.9224765617. The cubic root of 256669957 is about 635.5138395727.

The spelling of 256669957 in words is "two hundred fifty-six million, six hundred sixty-nine thousand, nine hundred fifty-seven".