856617659 has 2 divisors, whose sum is σ = 856617660. Its totient is φ = 856617658.

The previous prime is 856617653. The next prime is 856617677. The reversal of 856617659 is 956716658.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-856617659 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 856617659.

It is not a weakly prime, because it can be changed into another prime (856617653) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 428308829 + 428308830.

It is an arithmetic number, because the mean of its divisors is an integer number (428308830).

Almost surely, 2^856617659 is an apocalyptic number.

856617659 is a deficient number, since it is larger than the sum of its proper divisors (1).

856617659 is an equidigital number, since it uses as much as digits as its factorization.

856617659 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2721600, while the sum is 53.

The square root of 856617659 is about 29268.0313482134. The cubic root of 856617659 is about 949.7201979308.

The spelling of 856617659 in words is "eight hundred fifty-six million, six hundred seventeen thousand, six hundred fifty-nine".