256731911 has 8 divisors (see below), whose sum is σ = 268134624. Its totient is φ = 245349280.

The previous prime is 256731901. The next prime is 256731919. The reversal of 256731911 is 119137652.

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

It is not a de Polignac number, because 256731911 - 2⁶ = 256731847 is a prime.

It is a super-2 number, since 2×256731911² = 131822548251423842, 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 (256731919) 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, 25001 + ... + 33741.

It is an arithmetic number, because the mean of its divisors is an integer number (33516828).

Almost surely, 2^256731911 is an apocalyptic number.

256731911 is a deficient number, since it is larger than the sum of its proper divisors (11402713).

256731911 is a wasteful number, since it uses less digits than its factorization.

256731911 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10041.

The product of its digits is 11340, while the sum is 35.

The square root of 256731911 is about 16022.8558940034. The cubic root of 256731911 is about 635.5649680821.

The spelling of 256731911 in words is "two hundred fifty-six million, seven hundred thirty-one thousand, nine hundred eleven".