256344617 has 2 divisors, whose sum is σ = 256344618. Its totient is φ = 256344616.

The previous prime is 256344607. The next prime is 256344643. The reversal of 256344617 is 716443652.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 215179561 + 41165056 = 14669^2 + 6416^2 .

It is a cyclic number.

It is not a de Polignac number, because 256344617 - 2¹² = 256340521 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (256344607) 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, 128172308 + 128172309.

It is an arithmetic number, because the mean of its divisors is an integer number (128172309).

Almost surely, 2^256344617 is an apocalyptic number.

It is an amenable number.

256344617 is a deficient number, since it is larger than the sum of its proper divisors (1).

256344617 is an equidigital number, since it uses as much as digits as its factorization.

256344617 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 120960, while the sum is 38.

The square root of 256344617 is about 16010.7656593931. The cubic root of 256344617 is about 635.2452125068.

The spelling of 256344617 in words is "two hundred fifty-six million, three hundred forty-four thousand, six hundred seventeen".