256317140 has 12 divisors (see below), whose sum is σ = 538266036. Its totient is φ = 102526848.

The previous prime is 256317137. The next prime is 256317209. The reversal of 256317140 is 41713652.

It can be written as a sum of positive squares in 2 ways, for example, as 123698884 + 132618256 = 11122^2 + 11516^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6407909 + ... + 6407948.

It is an arithmetic number, because the mean of its divisors is an integer number (44855503).

Almost surely, 2^256317140 is an apocalyptic number.

256317140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

256317140 is an abundant number, since it is smaller than the sum of its proper divisors (281948896).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

256317140 is a wasteful number, since it uses less digits than its factorization.

256317140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12815866 (or 12815864 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 29.

The square root of 256317140 is about 16009.9075575095. The cubic root of 256317140 is about 635.2225148631. Note that the first 3 decimals are identical.

The spelling of 256317140 in words is "two hundred fifty-six million, three hundred seventeen thousand, one hundred forty".