686635 has 8 divisors (see below), whose sum is σ = 833760. Its totient is φ = 542784.

The previous prime is 686611. The next prime is 686639. The reversal of 686635 is 536686.

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 686635 - 2¹¹ = 684587 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 686635.

It is not an unprimeable number, because it can be changed into a prime (686639) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 327 + ... + 1216.

It is an arithmetic number, because the mean of its divisors is an integer number (104220).

2⁶⁸⁶⁶³⁵ is an apocalyptic number.

686635 is a deficient number, since it is larger than the sum of its proper divisors (147125).

686635 is a wasteful number, since it uses less digits than its factorization.

686635 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1637.

The product of its digits is 25920, while the sum is 34.

The square root of 686635 is about 828.6344187879. The cubic root of 686635 is about 88.2216776810.

The spelling of 686635 in words is "six hundred eighty-six thousand, six hundred thirty-five".