666198 has 48 divisors (see below), whose sum is σ = 1625040. Its totient is φ = 202176.

The previous prime is 666191. The next prime is 666203. The reversal of 666198 is 891666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666191) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9090 + ... + 9162.

It is an arithmetic number, because the mean of its divisors is an integer number (33855).

2⁶⁶⁶¹⁹⁸ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 666198, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (812520).

666198 is an abundant number, since it is smaller than the sum of its proper divisors (958842).

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

666198 is a wasteful number, since it uses less digits than its factorization.

666198 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110 (or 91 counting only the distinct ones).

The product of its digits is 15552, while the sum is 36.

The square root of 666198 is about 816.2095319218. The cubic root of 666198 is about 87.3375707725.

The spelling of 666198 in words is "six hundred sixty-six thousand, one hundred ninety-eight".