256704439 has 2 divisors, whose sum is σ = 256704440. Its totient is φ = 256704438.

The previous prime is 256704401. The next prime is 256704451. The reversal of 256704439 is 934407652.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-256704439 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256704139) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128352219 + 128352220.

It is an arithmetic number, because the mean of its divisors is an integer number (128352220).

Almost surely, 2^256704439 is an apocalyptic number.

256704439 is a deficient number, since it is larger than the sum of its proper divisors (1).

256704439 is an equidigital number, since it uses as much as digits as its factorization.

256704439 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 181440, while the sum is 40.

The square root of 256704439 is about 16021.9985956809. The cubic root of 256704439 is about 635.5422973987.

The spelling of 256704439 in words is "two hundred fifty-six million, seven hundred four thousand, four hundred thirty-nine".