667404 has 18 divisors (see below), whose sum is σ = 1687140. Its totient is φ = 222456.

The previous prime is 667379. The next prime is 667417. The reversal of 667404 is 404766.

It is a tau number, because it is divible by the number of its divisors (18).

It is an unprimeable number.

667404 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 5 ways as a sum of consecutive naturals, for example, 9234 + ... + 9305.

It is an arithmetic number, because the mean of its divisors is an integer number (93730).

2⁶⁶⁷⁴⁰⁴ is an apocalyptic number.

It is an amenable number.

667404 is an abundant number, since it is smaller than the sum of its proper divisors (1019736).

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

667404 is a wasteful number, since it uses less digits than its factorization.

667404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18549 (or 18544 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 27.

The square root of 667404 is about 816.9479787600. The cubic root of 667404 is about 87.3902406074.

The spelling of 667404 in words is "six hundred sixty-seven thousand, four hundred four".