256743504214217 has 2 divisors, whose sum is σ = 256743504214218. Its totient is φ = 256743504214216.

The previous prime is 256743504214189. The next prime is 256743504214283. The reversal of 256743504214217 is 712412405347652.

256743504214217 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., 209034313404361 + 47709190809856 = 14458019^2 + 6907184^2 .

It is a cyclic number.

It is not a de Polignac number, because 256743504214217 - 2¹⁴ = 256743504197833 is a prime.

It is not a weakly prime, because it can be changed into another prime (256743504210217) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128371752107108 + 128371752107109.

It is an arithmetic number, because the mean of its divisors is an integer number (128371752107109).

Almost surely, 2^{256743504214217} is an apocalyptic number.

It is an amenable number.

256743504214217 is a deficient number, since it is larger than the sum of its proper divisors (1).

256743504214217 is an equidigital number, since it uses as much as digits as its factorization.

256743504214217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11289600, while the sum is 53.

The spelling of 256743504214217 in words is "two hundred fifty-six trillion, seven hundred forty-three billion, five hundred four million, two hundred fourteen thousand, two hundred seventeen".