666328 has 32 divisors (see below), whose sum is σ = 1386000. Its totient is φ = 298368.

The previous prime is 666301. The next prime is 666329. The reversal of 666328 is 823666.

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

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 666328.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666329) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4398 + ... + 4546.

2⁶⁶⁶³²⁸ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 666328, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (693000).

666328 is an abundant number, since it is smaller than the sum of its proper divisors (719672).

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

666328 is a wasteful number, since it uses less digits than its factorization.

666328 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 211 (or 207 counting only the distinct ones).

The product of its digits is 10368, while the sum is 31.

The square root of 666328 is about 816.2891644509. The cubic root of 666328 is about 87.3432513388.

The spelling of 666328 in words is "six hundred sixty-six thousand, three hundred twenty-eight".