685917 has 6 divisors (see below), whose sum is σ = 990782. Its totient is φ = 457272.

The previous prime is 685907. The next prime is 685939. The reversal of 685917 is 719586.

685917 is a `hidden beast` number, since 68 + 591 + 7 = 666.

It can be written as a sum of positive squares in only one way, i.e., 617796 + 68121 = 786^2 + 261^2 .

It is a de Polignac number, because none of the positive numbers 2^k-685917 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 685917.

It is not an unprimeable number, because it can be changed into a prime (685907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 38098 + ... + 38115.

2⁶⁸⁵⁹¹⁷ is an apocalyptic number.

It is an amenable number.

685917 is a deficient number, since it is larger than the sum of its proper divisors (304865).

685917 is a wasteful number, since it uses less digits than its factorization.

685917 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76219 (or 76216 counting only the distinct ones).

The product of its digits is 15120, while the sum is 36.

The square root of 685917 is about 828.2010625446. The cubic root of 685917 is about 88.1909164292.

The spelling of 685917 in words is "six hundred eighty-five thousand, nine hundred seventeen".