687704 has 32 divisors (see below), whose sum is σ = 1382400. Its totient is φ = 320160.

The previous prime is 687691. The next prime is 687707. The reversal of 687704 is 407786.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (687707) by changing a digit.

687704 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 7 ways as a sum of consecutive naturals, for example, 11627 + ... + 11685.

It is an arithmetic number, because the mean of its divisors is an integer number (43200).

2⁶⁸⁷⁷⁰⁴ is an apocalyptic number.

It is an amenable number.

687704 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

687704 is a wasteful number, since it uses less digits than its factorization.

687704 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143 (or 139 counting only the distinct ones).

The product of its (nonzero) digits is 9408, while the sum is 32.

The square root of 687704 is about 829.2792050932. The cubic root of 687704 is about 88.2674371085.

The spelling of 687704 in words is "six hundred eighty-seven thousand, seven hundred four".