256517413647413 has 2 divisors, whose sum is σ = 256517413647414. Its totient is φ = 256517413647412.

The previous prime is 256517413647353. The next prime is 256517413647431. The reversal of 256517413647413 is 314746314715652.

It is a happy number.

256517413647413 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

Together with next prime (256517413647431) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 238563871833169 + 17953541814244 = 15445513^2 + 4237162^2 .

It is a cyclic number.

It is not a de Polignac number, because 256517413647413 - 2⁴² = 252119367136309 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256517413647433) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128258706823706 + 128258706823707.

It is an arithmetic number, because the mean of its divisors is an integer number (128258706823707).

Almost surely, 2^{256517413647413} is an apocalyptic number.

It is an amenable number.

256517413647413 is a deficient number, since it is larger than the sum of its proper divisors (1).

256517413647413 is an equidigital number, since it uses as much as digits as its factorization.

256517413647413 is an evil number, because the sum of its binary digits is even.

The product of its digits is 50803200, while the sum is 59.

The spelling of 256517413647413 in words is "two hundred fifty-six trillion, five hundred seventeen billion, four hundred thirteen million, six hundred forty-seven thousand, four hundred thirteen".