256611366645071 has 4 divisors (see below), whose sum is σ = 256611462769032. Its totient is φ = 256611270521112.

The previous prime is 256611366645031. The next prime is 256611366645077. The reversal of 256611366645071 is 170546663116652.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-256611366645071 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 256611366645071.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256611366645077) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 43939745 + ... + 49436058.

It is an arithmetic number, because the mean of its divisors is an integer number (64152865692258).

Almost surely, 2^{256611366645071} is an apocalyptic number.

256611366645071 is a deficient number, since it is larger than the sum of its proper divisors (96123961).

256611366645071 is an equidigital number, since it uses as much as digits as its factorization.

256611366645071 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96123960.

The product of its (nonzero) digits is 32659200, while the sum is 59.

The spelling of 256611366645071 in words is "two hundred fifty-six trillion, six hundred eleven billion, three hundred sixty-six million, six hundred forty-five thousand, seventy-one".