256797647 has 2 divisors, whose sum is σ = 256797648. Its totient is φ = 256797646.

The previous prime is 256797641. The next prime is 256797661. The reversal of 256797647 is 746797652.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 256797647 - 2¹⁴ = 256781263 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 (256797641) 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, 128398823 + 128398824.

It is an arithmetic number, because the mean of its divisors is an integer number (128398824).

Almost surely, 2^256797647 is an apocalyptic number.

256797647 is a deficient number, since it is larger than the sum of its proper divisors (1).

256797647 is an equidigital number, since it uses as much as digits as its factorization.

256797647 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4445280, while the sum is 53.

The square root of 256797647 is about 16024.9070824139. The cubic root of 256797647 is about 635.6192087532.

The spelling of 256797647 in words is "two hundred fifty-six million, seven hundred ninety-seven thousand, six hundred forty-seven".