256682081 has 2 divisors, whose sum is σ = 256682082. Its totient is φ = 256682080.

The previous prime is 256682071. The next prime is 256682117. The reversal of 256682081 is 180286652.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 173580625 + 83101456 = 13175^2 + 9116^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-256682081 is a prime.

It is a super-2 number, since 2×256682081² = 131771381412981122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (256682011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128341040 + 128341041.

It is an arithmetic number, because the mean of its divisors is an integer number (128341041).

Almost surely, 2^256682081 is an apocalyptic number.

It is an amenable number.

256682081 is a deficient number, since it is larger than the sum of its proper divisors (1).

256682081 is an equidigital number, since it uses as much as digits as its factorization.

256682081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 46080, while the sum is 38.

The square root of 256682081 is about 16021.3008523028. The cubic root of 256682081 is about 635.5238457411.

The spelling of 256682081 in words is "two hundred fifty-six million, six hundred eighty-two thousand, eighty-one".