686018 has 8 divisors (see below), whose sum is σ = 1089612. Its totient is φ = 322816.

The previous prime is 686011. The next prime is 686027. The reversal of 686018 is 810686.

It can be written as a sum of positive squares in 2 ways, for example, as 644809 + 41209 = 803^2 + 203^2 .

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

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 686018.

It is not an unprimeable number, because it can be changed into a prime (686011) by changing a digit.

686018 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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 3 ways as a sum of consecutive naturals, for example, 10055 + ... + 10122.

2⁶⁸⁶⁰¹⁸ is an apocalyptic number.

686018 is a deficient number, since it is larger than the sum of its proper divisors (403594).

686018 is a wasteful number, since it uses less digits than its factorization.

686018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20196.

The product of its (nonzero) digits is 2304, while the sum is 29.

The square root of 686018 is about 828.2620358317. The cubic root of 686018 is about 88.1952448661.

The spelling of 686018 in words is "six hundred eighty-six thousand, eighteen".