256864547 has 2 divisors, whose sum is σ = 256864548. Its totient is φ = 256864546.

The previous prime is 256864501. The next prime is 256864567. The reversal of 256864547 is 745468652.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 256864547 - 2⁸ = 256864291 is a prime.

It is not a weakly prime, because it can be changed into another prime (256864567) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128432273 + 128432274.

It is an arithmetic number, because the mean of its divisors is an integer number (128432274).

Almost surely, 2^256864547 is an apocalyptic number.

256864547 is a deficient number, since it is larger than the sum of its proper divisors (1).

256864547 is an equidigital number, since it uses as much as digits as its factorization.

256864547 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1612800, while the sum is 47.

The square root of 256864547 is about 16026.9943220805. The cubic root of 256864547 is about 635.6744003712.

The spelling of 256864547 in words is "two hundred fifty-six million, eight hundred sixty-four thousand, five hundred forty-seven".