678666 has 8 divisors (see below), whose sum is σ = 1357344. Its totient is φ = 226220.

The previous prime is 678659. The next prime is 678719. The reversal of 678666 is 666876.

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

678666 is an admirable number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 56550 + ... + 56561.

It is an arithmetic number, because the mean of its divisors is an integer number (169668).

2⁶⁷⁸⁶⁶⁶ is an apocalyptic number.

678666 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.

678666 is a wasteful number, since it uses less digits than its factorization.

678666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 113116.

The product of its digits is 72576, while the sum is 39.

The square root of 678666 is about 823.8118717280. The cubic root of 678666 is about 87.8790521641.

The spelling of 678666 in words is "six hundred seventy-eight thousand, six hundred sixty-six".