686601 has 6 divisors (see below), whose sum is σ = 991770. Its totient is φ = 457728.

The previous prime is 686593. The next prime is 686611. The reversal of 686601 is 106686.

It can be written as a sum of positive squares in only one way, i.e., 435600 + 251001 = 660^2 + 501^2 .

It is not a de Polignac number, because 686601 - 2³ = 686593 is a prime.

It is not an unprimeable number, because it can be changed into a prime (686611) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 38136 + ... + 38153.

It is an arithmetic number, because the mean of its divisors is an integer number (165295).

2⁶⁸⁶⁶⁰¹ is an apocalyptic number.

It is an amenable number.

686601 is a deficient number, since it is larger than the sum of its proper divisors (305169).

686601 is a wasteful number, since it uses less digits than its factorization.

686601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76295 (or 76292 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 686601 is about 828.6139028522. The cubic root of 686601 is about 88.2202215038.

The spelling of 686601 in words is "six hundred eighty-six thousand, six hundred one".