685139 has 8 divisors (see below), whose sum is σ = 843360. Its totient is φ = 542016.

The previous prime is 685123. The next prime is 685141. The reversal of 685139 is 931586.

685139 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 685139 - 2⁴ = 685123 is a prime.

It is not an unprimeable number, because it can be changed into a prime (685109) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3674 + ... + 3855.

It is an arithmetic number, because the mean of its divisors is an integer number (105420).

2⁶⁸⁵¹³⁹ is an apocalyptic number.

685139 is a deficient number, since it is larger than the sum of its proper divisors (158221).

685139 is a wasteful number, since it uses less digits than its factorization.

685139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7549.

The product of its digits is 6480, while the sum is 32.

The square root of 685139 is about 827.7312365738. The cubic root of 685139 is about 88.1575603572.

The spelling of 685139 in words is "six hundred eighty-five thousand, one hundred thirty-nine".