678664 has 16 divisors (see below), whose sum is σ = 1454400. Its totient is φ = 290832.

The previous prime is 678659. The next prime is 678719. The reversal of 678664 is 466876.

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, 6004 + ... + 6115.

It is an arithmetic number, because the mean of its divisors is an integer number (90900).

2⁶⁷⁸⁶⁶⁴ is an apocalyptic number.

It is an amenable number.

678664 is an abundant number, since it is smaller than the sum of its proper divisors (775736).

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

678664 is a wasteful number, since it uses less digits than its factorization.

678664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12132 (or 12128 counting only the distinct ones).

The product of its digits is 48384, while the sum is 37.

The square root of 678664 is about 823.8106578577. The cubic root of 678664 is about 87.8789658388.

The spelling of 678664 in words is "six hundred seventy-eight thousand, six hundred sixty-four".