256511611 has 2 divisors, whose sum is σ = 256511612. Its totient is φ = 256511610.

The previous prime is 256511587. The next prime is 256511659. The reversal of 256511611 is 116115652.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 256511611 - 2⁵ = 256511579 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 256511611.

It is not a weakly prime, because it can be changed into another prime (256511911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128255805 + 128255806.

It is an arithmetic number, because the mean of its divisors is an integer number (128255806).

Almost surely, 2^256511611 is an apocalyptic number.

256511611 is a deficient number, since it is larger than the sum of its proper divisors (1).

256511611 is an equidigital number, since it uses as much as digits as its factorization.

256511611 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1800, while the sum is 28.

The square root of 256511611 is about 16015.9798638735. The cubic root of 256511611 is about 635.3831246569.

The spelling of 256511611 in words is "two hundred fifty-six million, five hundred eleven thousand, six hundred eleven".