668812 has 12 divisors (see below), whose sum is σ = 1202320. Its totient is φ = 325296.

The previous prime is 668803. The next prime is 668813. The reversal of 668812 is 218866.

It is a hoax number, since the sum of its digits (31) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (668813) by changing a digit.

668812 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2112 + ... + 2407.

2⁶⁶⁸⁸¹² is an apocalyptic number.

It is an amenable number.

668812 is a deficient number, since it is larger than the sum of its proper divisors (533508).

668812 is a wasteful number, since it uses less digits than its factorization.

668812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4560 (or 4558 counting only the distinct ones).

The product of its digits is 4608, while the sum is 31.

The square root of 668812 is about 817.8092687173. The cubic root of 668812 is about 87.4516522021.

The spelling of 668812 in words is "six hundred sixty-eight thousand, eight hundred twelve".