856717 has 2 divisors, whose sum is σ = 856718. Its totient is φ = 856716.

The previous prime is 856711. The next prime is 856721. The reversal of 856717 is 717658.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 509796 + 346921 = 714^2 + 589^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-856717 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (856711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 428358 + 428359.

It is an arithmetic number, because the mean of its divisors is an integer number (428359).

2⁸⁵⁶⁷¹⁷ is an apocalyptic number.

It is an amenable number.

856717 is a deficient number, since it is larger than the sum of its proper divisors (1).

856717 is an equidigital number, since it uses as much as digits as its factorization.

856717 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 11760, while the sum is 34.

The square root of 856717 is about 925.5900820558. The cubic root of 856717 is about 94.9756909178.

The spelling of 856717 in words is "eight hundred fifty-six thousand, seven hundred seventeen".