256626089 has 2 divisors, whose sum is σ = 256626090. Its totient is φ = 256626088.

The previous prime is 256626047. The next prime is 256626113. The reversal of 256626089 is 980626652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 224760064 + 31866025 = 14992^2 + 5645^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-256626089 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (256626389) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128313044 + 128313045.

It is an arithmetic number, because the mean of its divisors is an integer number (128313045).

Almost surely, 2^256626089 is an apocalyptic number.

It is an amenable number.

256626089 is a deficient number, since it is larger than the sum of its proper divisors (1).

256626089 is an equidigital number, since it uses as much as digits as its factorization.

256626089 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 311040, while the sum is 44.

The square root of 256626089 is about 16019.5533333486. The cubic root of 256626089 is about 635.4776318426.

The spelling of 256626089 in words is "two hundred fifty-six million, six hundred twenty-six thousand, eighty-nine".