198665971 has 8 divisors (see below), whose sum is σ = 227324160. Its totient is φ = 170077128.

The previous prime is 198665969. The next prime is 198665993. The reversal of 198665971 is 179566891.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 198665971 - 2¹ = 198665969 is a prime.

It is not an unprimeable number, because it can be changed into a prime (198665941) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11041 + ... + 22786.

It is an arithmetic number, because the mean of its divisors is an integer number (28415520).

Almost surely, 2^198665971 is an apocalyptic number.

198665971 is a deficient number, since it is larger than the sum of its proper divisors (28658189).

198665971 is an equidigital number, since it uses as much as digits as its factorization.

198665971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34673.

The product of its digits is 816480, while the sum is 52.

The square root of 198665971 is about 14094.8916632942. The cubic root of 198665971 is about 583.5004044624.

The spelling of 198665971 in words is "one hundred ninety-eight million, six hundred sixty-five thousand, nine hundred seventy-one".