687986 has 16 divisors (see below), whose sum is σ = 1137024. Its totient is φ = 310224.

The previous prime is 687977. The next prime is 688003. The reversal of 687986 is 689786.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 687986.

It is an unprimeable number.

687986 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 (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 941 + ... + 1503.

It is an arithmetic number, because the mean of its divisors is an integer number (71064).

2⁶⁸⁷⁹⁸⁶ is an apocalyptic number.

687986 is a deficient number, since it is larger than the sum of its proper divisors (449038).

687986 is a wasteful number, since it uses less digits than its factorization.

687986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 625.

The product of its digits is 145152, while the sum is 44.

The square root of 687986 is about 829.4492148408. The cubic root of 687986 is about 88.2795004457.

The spelling of 687986 in words is "six hundred eighty-seven thousand, nine hundred eighty-six".