686642 has 24 divisors (see below), whose sum is σ = 1194480. Its totient is φ = 293480.

The previous prime is 686639. The next prime is 686669. The reversal of 686642 is 246686.

It is a happy number.

686642 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 686599 and 686608.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11609 + ... + 11667.

It is an arithmetic number, because the mean of its divisors is an integer number (49770).

2⁶⁸⁶⁶⁴² is an apocalyptic number.

686642 is a deficient number, since it is larger than the sum of its proper divisors (507838).

686642 is a wasteful number, since it uses less digits than its factorization.

686642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118 (or 95 counting only the distinct ones).

The product of its digits is 13824, while the sum is 32.

The square root of 686642 is about 828.6386425940. The cubic root of 686642 is about 88.2219774762.

The spelling of 686642 in words is "six hundred eighty-six thousand, six hundred forty-two".