665566198 has 16 divisors (see below), whose sum is σ = 1097426880. Its totient is φ = 300219400.

The previous prime is 665566193. The next prime is 665566207. The reversal of 665566198 is 891665566.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665566193) 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, 112588 + ... + 118351.

It is an arithmetic number, because the mean of its divisors is an integer number (68589180).

Almost surely, 2^665566198 is an apocalyptic number.

665566198 is a deficient number, since it is larger than the sum of its proper divisors (431860682).

665566198 is a wasteful number, since it uses less digits than its factorization.

665566198 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 231083.

The product of its digits is 2332800, while the sum is 52.

The square root of 665566198 is about 25798.5696890351. The cubic root of 665566198 is about 873.0995260455.

The spelling of 665566198 in words is "six hundred sixty-five million, five hundred sixty-six thousand, one hundred ninety-eight".