666704 has 10 divisors (see below), whose sum is σ = 1291770. Its totient is φ = 333344.

The previous prime is 666697. The next prime is 666707. The reversal of 666704 is 407666.

It can be written as a sum of positive squares in only one way, i.e., 462400 + 204304 = 680^2 + 452^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666707) by changing a digit.

666704 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20819 + ... + 20850.

It is an arithmetic number, because the mean of its divisors is an integer number (129177).

2⁶⁶⁶⁷⁰⁴ is an apocalyptic number.

It is an amenable number.

666704 is a deficient number, since it is larger than the sum of its proper divisors (625066).

666704 is a wasteful number, since it uses less digits than its factorization.

666704 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41677 (or 41671 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 29.

The square root of 666704 is about 816.5194425119. The cubic root of 666704 is about 87.3596771267.

It can be divided in two parts, 666 and 704, that multiplied together give a palindrome (468864).

The spelling of 666704 in words is "six hundred sixty-six thousand, seven hundred four".