256324517 has 2 divisors, whose sum is σ = 256324518. Its totient is φ = 256324516.

The previous prime is 256324477. The next prime is 256324531. The reversal of 256324517 is 715423652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 134420836 + 121903681 = 11594^2 + 11041^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-256324517 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 (256324577) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128162258 + 128162259.

It is an arithmetic number, because the mean of its divisors is an integer number (128162259).

Almost surely, 2^256324517 is an apocalyptic number.

It is an amenable number.

256324517 is a deficient number, since it is larger than the sum of its proper divisors (1).

256324517 is an equidigital number, since it uses as much as digits as its factorization.

256324517 is an evil number, because the sum of its binary digits is even.

The product of its digits is 50400, while the sum is 35.

The square root of 256324517 is about 16010.1379444401. The cubic root of 256324517 is about 635.2286088651.

The spelling of 256324517 in words is "two hundred fifty-six million, three hundred twenty-four thousand, five hundred seventeen".