666504 has 24 divisors (see below), whose sum is σ = 1805310. Its totient is φ = 222144.

The previous prime is 666493. The next prime is 666511. The reversal of 666504 is 405666.

It can be written as a sum of positive squares in only one way, i.e., 656100 + 10404 = 810^2 + 102^2 .

It is a tau number, because it is divible by the number of its divisors (24).

It is an unprimeable number.

666504 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, 4557 + ... + 4700.

2⁶⁶⁶⁵⁰⁴ is an apocalyptic number.

It is an amenable number.

666504 is an abundant number, since it is smaller than the sum of its proper divisors (1138806).

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

666504 is a wasteful number, since it uses less digits than its factorization.

666504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9269 (or 9262 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 666504 is about 816.3969622677. The cubic root of 666504 is about 87.3509407746.

The spelling of 666504 in words is "six hundred sixty-six thousand, five hundred four".