256698287 has 2 divisors, whose sum is σ = 256698288. Its totient is φ = 256698286.

The previous prime is 256698241. The next prime is 256698307. The reversal of 256698287 is 782896652.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 256698287 - 2⁶ = 256698223 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256698217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128349143 + 128349144.

It is an arithmetic number, because the mean of its divisors is an integer number (128349144).

Almost surely, 2^256698287 is an apocalyptic number.

256698287 is a deficient number, since it is larger than the sum of its proper divisors (1).

256698287 is an equidigital number, since it uses as much as digits as its factorization.

256698287 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2903040, while the sum is 53.

The square root of 256698287 is about 16021.8066084946. The cubic root of 256698287 is about 635.5372203700.

The spelling of 256698287 in words is "two hundred fifty-six million, six hundred ninety-eight thousand, two hundred eighty-seven".