256337321 has 2 divisors, whose sum is σ = 256337322. Its totient is φ = 256337320.

The previous prime is 256337287. The next prime is 256337327. The reversal of 256337321 is 123733652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 170589721 + 85747600 = 13061^2 + 9260^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-256337321 is a prime.

It is not a weakly prime, because it can be changed into another prime (256337327) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128168660 + 128168661.

It is an arithmetic number, because the mean of its divisors is an integer number (128168661).

Almost surely, 2^256337321 is an apocalyptic number.

It is an amenable number.

256337321 is a deficient number, since it is larger than the sum of its proper divisors (1).

256337321 is an equidigital number, since it uses as much as digits as its factorization.

256337321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 22680, while the sum is 32.

The square root of 256337321 is about 16010.5378110793. The cubic root of 256337321 is about 635.2391857330.

The spelling of 256337321 in words is "two hundred fifty-six million, three hundred thirty-seven thousand, three hundred twenty-one".