256507313 has 2 divisors, whose sum is σ = 256507314. Its totient is φ = 256507312.

The previous prime is 256507297. The next prime is 256507337. The reversal of 256507313 is 313705652.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 247338529 + 9168784 = 15727^2 + 3028^2 .

It is a cyclic number.

It is not a de Polignac number, because 256507313 - 2⁴ = 256507297 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 256507313.

It is not a weakly prime, because it can be changed into another prime (256507343) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128253656 + 128253657.

It is an arithmetic number, because the mean of its divisors is an integer number (128253657).

Almost surely, 2^256507313 is an apocalyptic number.

It is an amenable number.

256507313 is a deficient number, since it is larger than the sum of its proper divisors (1).

256507313 is an equidigital number, since it uses as much as digits as its factorization.

256507313 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18900, while the sum is 32.

The square root of 256507313 is about 16015.8456848210. The cubic root of 256507313 is about 635.3795759001.

The spelling of 256507313 in words is "two hundred fifty-six million, five hundred seven thousand, three hundred thirteen".