685839 has 16 divisors (see below), whose sum is σ = 1140480. Its totient is φ = 356160.

The previous prime is 685819. The next prime is 685849. The reversal of 685839 is 938586.

It is not a de Polignac number, because 685839 - 2¹³ = 677647 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 685797 and 685806.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (685819) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1254 + ... + 1715.

It is an arithmetic number, because the mean of its divisors is an integer number (71280).

2⁶⁸⁵⁸³⁹ is an apocalyptic number.

685839 is a deficient number, since it is larger than the sum of its proper divisors (454641).

685839 is a wasteful number, since it uses less digits than its factorization.

685839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2990.

The product of its digits is 51840, while the sum is 39.

The square root of 685839 is about 828.1539711913. The cubic root of 685839 is about 88.1875733852.

The spelling of 685839 in words is "six hundred eighty-five thousand, eight hundred thirty-nine".