256717361 has 2 divisors, whose sum is σ = 256717362. Its totient is φ = 256717360.

The previous prime is 256717343. The next prime is 256717381. The reversal of 256717361 is 163717652.

256717361 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 200392336 + 56325025 = 14156^2 + 7505^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-256717361 is a prime.

It is not a weakly prime, because it can be changed into another prime (256717381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128358680 + 128358681.

It is an arithmetic number, because the mean of its divisors is an integer number (128358681).

Almost surely, 2^256717361 is an apocalyptic number.

It is an amenable number.

256717361 is a deficient number, since it is larger than the sum of its proper divisors (1).

256717361 is an equidigital number, since it uses as much as digits as its factorization.

256717361 is an evil number, because the sum of its binary digits is even.

The product of its digits is 52920, while the sum is 38.

The square root of 256717361 is about 16022.4018486618. The cubic root of 256717361 is about 635.5529612057.

The spelling of 256717361 in words is "two hundred fifty-six million, seven hundred seventeen thousand, three hundred sixty-one".