198879191 has 12 divisors (see below), whose sum is σ = 231595560. Its totient is φ = 170286480.

The previous prime is 198879173. The next prime is 198879199. The reversal of 198879191 is 191978891.

It is not a de Polignac number, because 198879191 - 2¹⁸ = 198617047 is a prime.

It is a super-2 number, since 2×198879191² = 79105865225628962, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (198879199) 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 11 ways as a sum of consecutive naturals, for example, 66200 + ... + 69138.

It is an arithmetic number, because the mean of its divisors is an integer number (19299630).

Almost surely, 2^198879191 is an apocalyptic number.

198879191 is a deficient number, since it is larger than the sum of its proper divisors (32716369).

198879191 is a wasteful number, since it uses less digits than its factorization.

198879191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4334 (or 4327 counting only the distinct ones).

The product of its digits is 326592, while the sum is 53.

The square root of 198879191 is about 14102.4533681200. The cubic root of 198879191 is about 583.7090788061.

The spelling of 198879191 in words is "one hundred ninety-eight million, eight hundred seventy-nine thousand, one hundred ninety-one".