666597198 has 16 divisors (see below), whose sum is σ = 1336458960. Its totient is φ = 221654976.

The previous prime is 666597133. The next prime is 666597209. The reversal of 666597198 is 891795666.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 133365 + ... + 138272.

It is an arithmetic number, because the mean of its divisors is an integer number (83528685).

Almost surely, 2^666597198 is an apocalyptic number.

666597198 is an abundant number, since it is smaller than the sum of its proper divisors (669861762).

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

666597198 is a wasteful number, since it uses less digits than its factorization.

666597198 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 272051.

The product of its digits is 4898880, while the sum is 57.

The square root of 666597198 is about 25818.5436847240. The cubic root of 666597198 is about 873.5501204472.

The spelling of 666597198 in words is "six hundred sixty-six million, five hundred ninety-seven thousand, one hundred ninety-eight".