256957389 has 24 divisors (see below), whose sum is σ = 402135552. Its totient is φ = 157168800.

The previous prime is 256957361. The next prime is 256957391. The reversal of 256957389 is 983759652.

256957389 is a `hidden beast` number, since 2 + 5 + 69 + 573 + 8 + 9 = 666.

It is not a de Polignac number, because 256957389 - 2⁸ = 256957133 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256957339) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12964 + ... + 26114.

It is an arithmetic number, because the mean of its divisors is an integer number (16755648).

Almost surely, 2^256957389 is an apocalyptic number.

It is an amenable number.

256957389 is a deficient number, since it is larger than the sum of its proper divisors (145178163).

256957389 is a wasteful number, since it uses less digits than its factorization.

256957389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13337 (or 13334 counting only the distinct ones).

The product of its digits is 4082400, while the sum is 54.

The square root of 256957389 is about 16029.8904862136. The cubic root of 256957389 is about 635.7509779220.

The spelling of 256957389 in words is "two hundred fifty-six million, nine hundred fifty-seven thousand, three hundred eighty-nine".