256681843507267 has 2 divisors, whose sum is σ = 256681843507268. Its totient is φ = 256681843507266.

The previous prime is 256681843507169. The next prime is 256681843507273. The reversal of 256681843507267 is 762705348186652.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 256681843507267 - 2³⁹ = 256132087693379 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 256681843507196 and 256681843507205.

It is not a weakly prime, because it can be changed into another prime (256681843207267) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128340921753633 + 128340921753634.

It is an arithmetic number, because the mean of its divisors is an integer number (128340921753634).

Almost surely, 2^{256681843507267} is an apocalyptic number.

256681843507267 is a deficient number, since it is larger than the sum of its proper divisors (1).

256681843507267 is an equidigital number, since it uses as much as digits as its factorization.

256681843507267 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 812851200, while the sum is 70.

The spelling of 256681843507267 in words is "two hundred fifty-six trillion, six hundred eighty-one billion, eight hundred forty-three million, five hundred seven thousand, two hundred sixty-seven".