685678 has 32 divisors (see below), whose sum is σ = 1292544. Its totient is φ = 266112.

The previous prime is 685669. The next prime is 685679. The reversal of 685678 is 876586.

It is a self number, because there is not a number n which added to its sum of digits gives 685678.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (685679) by changing a digit.

685678 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10201 + ... + 10267.

It is an arithmetic number, because the mean of its divisors is an integer number (40392).

2⁶⁸⁵⁶⁷⁸ is an apocalyptic number.

685678 is a deficient number, since it is larger than the sum of its proper divisors (606866).

685678 is a wasteful number, since it uses less digits than its factorization.

685678 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136.

The product of its digits is 80640, while the sum is 40.

The square root of 685678 is about 828.0567613395. The cubic root of 685678 is about 88.1806721977.

The spelling of 685678 in words is "six hundred eighty-five thousand, six hundred seventy-eight".