678986 has 16 divisors (see below), whose sum is σ = 1270080. Its totient is φ = 264480.

The previous prime is 678971. The next prime is 678989. The reversal of 678986 is 689876.

678986 = T₂₈ + T₂₉ + ... + T₁₅₉.

It is a super-2 number, since 2×678986² = 922043976392, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (678989) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2051 + ... + 2358.

It is an arithmetic number, because the mean of its divisors is an integer number (79380).

2⁶⁷⁸⁹⁸⁶ is an apocalyptic number.

678986 is a deficient number, since it is larger than the sum of its proper divisors (591094).

678986 is a wasteful number, since it uses less digits than its factorization.

678986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4429.

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

The square root of 678986 is about 824.0060679388. The cubic root of 678986 is about 87.8928620392.

The spelling of 678986 in words is "six hundred seventy-eight thousand, nine hundred eighty-six".