256662881 has 2 divisors, whose sum is σ = 256662882. Its totient is φ = 256662880.

The previous prime is 256662869. The next prime is 256662893. The reversal of 256662881 is 188266652.

It is a balanced prime because it is at equal distance from previous prime (256662869) and next prime (256662893).

It can be written as a sum of positive squares in only one way, i.e., 219513856 + 37149025 = 14816^2 + 6095^2 .

It is a cyclic number.

It is not a de Polignac number, because 256662881 - 2¹⁰ = 256661857 is a prime.

It is a super-2 number, since 2×256662881² = 131751668966440322, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (256662841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128331440 + 128331441.

It is an arithmetic number, because the mean of its divisors is an integer number (128331441).

Almost surely, 2^256662881 is an apocalyptic number.

It is an amenable number.

256662881 is a deficient number, since it is larger than the sum of its proper divisors (1).

256662881 is an equidigital number, since it uses as much as digits as its factorization.

256662881 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 276480, while the sum is 44.

The square root of 256662881 is about 16020.7016388172. The cubic root of 256662881 is about 635.5079994693.

The spelling of 256662881 in words is "two hundred fifty-six million, six hundred sixty-two thousand, eight hundred eighty-one".