19999800198 has 24 divisors (see below), whose sum is σ = 49523315088. Its totient is φ = 5714228592.

The previous prime is 19999800193. The next prime is 19999800199. The reversal of 19999800198 is 89100899991.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19999800193) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 79364161 + ... + 79364412.

It is an arithmetic number, because the mean of its divisors is an integer number (2063471462).

Almost surely, 2^19999800198 is an apocalyptic number.

19999800198 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

19999800198 is an abundant number, since it is smaller than the sum of its proper divisors (29523514890).

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

19999800198 is a wasteful number, since it uses less digits than its factorization.

19999800198 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 158728588 (or 158728585 counting only the distinct ones).

The product of its (nonzero) digits is 3779136, while the sum is 63.

The spelling of 19999800198 in words is "nineteen billion, nine hundred ninety-nine million, eight hundred thousand, one hundred ninety-eight".