256402567 has 2 divisors, whose sum is σ = 256402568. Its totient is φ = 256402566.

The previous prime is 256402529. The next prime is 256402571. The reversal of 256402567 is 765204652.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 256402567 - 2²³ = 248013959 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256402577) 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, 128201283 + 128201284.

It is an arithmetic number, because the mean of its divisors is an integer number (128201284).

Almost surely, 2^256402567 is an apocalyptic number.

256402567 is a deficient number, since it is larger than the sum of its proper divisors (1).

256402567 is an equidigital number, since it uses as much as digits as its factorization.

256402567 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 100800, while the sum is 37.

The square root of 256402567 is about 16012.5752769503. The cubic root of 256402567 is about 635.2930773523.

The spelling of 256402567 in words is "two hundred fifty-six million, four hundred two thousand, five hundred sixty-seven".