685791 has 12 divisors (see below), whose sum is σ = 1033968. Its totient is φ = 437184.

The previous prime is 685781. The next prime is 685793. The reversal of 685791 is 197586.

It is not a de Polignac number, because 685791 - 2⁵ = 685759 is a prime.

685791 is a lucky 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 685791.

It is not an unprimeable number, because it can be changed into a prime (685793) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1450 + ... + 1863.

It is an arithmetic number, because the mean of its divisors is an integer number (86164).

2⁶⁸⁵⁷⁹¹ is an apocalyptic number.

685791 is a deficient number, since it is larger than the sum of its proper divisors (348177).

685791 is a wasteful number, since it uses less digits than its factorization.

685791 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3342 (or 3339 counting only the distinct ones).

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

The square root of 685791 is about 828.1249905660. The cubic root of 685791 is about 88.1855160013.

The spelling of 685791 in words is "six hundred eighty-five thousand, seven hundred ninety-one".