256631115 has 32 divisors (see below), whose sum is σ = 442987776. Its totient is φ = 126115200.

The previous prime is 256631107. The next prime is 256631143. The reversal of 256631115 is 511136652.

It is not a de Polignac number, because 256631115 - 2³ = 256631107 is a prime.

It is a super-2 number, since 2×256631115² = 131719058372286450, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 176140 + ... + 177590.

It is an arithmetic number, because the mean of its divisors is an integer number (13843368).

Almost surely, 2^256631115 is an apocalyptic number.

256631115 is a deficient number, since it is larger than the sum of its proper divisors (186356661).

256631115 is a wasteful number, since it uses less digits than its factorization.

256631115 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2379.

The product of its digits is 5400, while the sum is 30.

The square root of 256631115 is about 16019.7102033713. The cubic root of 256631115 is about 635.4817804072.

Adding to 256631115 its reverse (511136652), we get a palindrome (767767767).

The spelling of 256631115 in words is "two hundred fifty-six million, six hundred thirty-one thousand, one hundred fifteen".