256791031 has 8 divisors (see below), whose sum is σ = 296073504. Its totient is φ = 218158080.

The previous prime is 256791013. The next prime is 256791049. The reversal of 256791031 is 130197652.

It is an interprime number because it is at equal distance from previous prime (256791013) and next prime (256791049).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 256791031 - 2⁷ = 256790903 is a prime.

It is a super-2 number, since 2×256791031² = 131883267204085922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256791131) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 161530 + ... + 163111.

It is an arithmetic number, because the mean of its divisors is an integer number (37009188).

Almost surely, 2^256791031 is an apocalyptic number.

256791031 is a deficient number, since it is larger than the sum of its proper divisors (39282473).

256791031 is a wasteful number, since it uses less digits than its factorization.

256791031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 324761.

The product of its (nonzero) digits is 11340, while the sum is 34.

The square root of 256791031 is about 16024.7006524303. The cubic root of 256791031 is about 635.6137501195.

The spelling of 256791031 in words is "two hundred fifty-six million, seven hundred ninety-one thousand, thirty-one".