686728 has 16 divisors (see below), whose sum is σ = 1471680. Its totient is φ = 294288.

The previous prime is 686723. The next prime is 686729. The reversal of 686728 is 827686.

It is not an unprimeable number, because it can be changed into a prime (686723) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6076 + ... + 6187.

It is an arithmetic number, because the mean of its divisors is an integer number (91980).

2⁶⁸⁶⁷²⁸ is an apocalyptic number.

It is an amenable number.

686728 is an abundant number, since it is smaller than the sum of its proper divisors (784952).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

686728 is a wasteful number, since it uses less digits than its factorization.

686728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12276 (or 12272 counting only the distinct ones).

The product of its digits is 32256, while the sum is 37.

The square root of 686728 is about 828.6905333114. The cubic root of 686728 is about 88.2256605081.

The spelling of 686728 in words is "six hundred eighty-six thousand, seven hundred twenty-eight".