198199929991 has 8 divisors (see below), whose sum is σ = 226672951680. Its totient is φ = 169766594808.

The previous prime is 198199929979. The next prime is 198199930031. The reversal of 198199929991 is 199929991891.

It is a happy number.

198199929991 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 198199929991 - 2¹¹ = 198199927943 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (198199929691) 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, 9910921 + ... + 9930898.

It is an arithmetic number, because the mean of its divisors is an integer number (28334118960).

Almost surely, 2^198199929991 is an apocalyptic number.

198199929991 is a deficient number, since it is larger than the sum of its proper divisors (28473021689).

198199929991 is a wasteful number, since it uses less digits than its factorization.

198199929991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19843253.

The product of its digits is 76527504, while the sum is 76.

The spelling of 198199929991 in words is "one hundred ninety-eight billion, one hundred ninety-nine million, nine hundred twenty-nine thousand, nine hundred ninety-one".