256646544502131 has 40 divisors (see below), whose sum is σ = 438156658337024. Its totient is φ = 146654595560880.

The previous prime is 256646544502097. The next prime is 256646544502253. The reversal of 256646544502131 is 131205445646652.

256646544502131 is a `hidden beast` number, since 2 + 5 + 6 + 6 + 4 + 6 + 54 + 450 + 2 + 131 = 666.

It is not a de Polignac number, because 256646544502131 - 2⁷ = 256646544502003 is a prime.

It is a super-2 number, since 2×256646544502131² (a number of 30 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (256646544552131) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 175417416 + ... + 176874426.

Almost surely, 2^{256646544502131} is an apocalyptic number.

256646544502131 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

256646544502131 is a deficient number, since it is larger than the sum of its proper divisors (181510113834893).

256646544502131 is a wasteful number, since it uses less digits than its factorization.

256646544502131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1767693 (or 1767684 counting only the distinct ones).

The product of its (nonzero) digits is 20736000, while the sum is 54.

The spelling of 256646544502131 in words is "two hundred fifty-six trillion, six hundred forty-six billion, five hundred forty-four million, five hundred two thousand, one hundred thirty-one".