199999999998 has 24 divisors (see below), whose sum is σ = 433354194000. Its totient is φ = 66663457344.

The previous prime is 199999999949. The next prime is 200000000041. The reversal of 199999999998 is 899999999991.

It is a junction number, because it is equal to n+sod(n) for n = 199999999899 and 199999999908.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 133063 + ... + 646301.

It is an arithmetic number, because the mean of its divisors is an integer number (18056424750).

Almost surely, 2^199999999998 is an apocalyptic number.

199999999998 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

199999999998 is an abundant number, since it is smaller than the sum of its proper divisors (233354194002).

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

199999999998 is a wasteful number, since it uses less digits than its factorization.

199999999998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 534896 (or 534893 counting only the distinct ones).

The product of its digits is 27894275208, while the sum is 99.

It can be divided in two parts, 1 and 99999999998, that added together give a palindrome (99999999999).

The spelling of 199999999998 in words is "one hundred ninety-nine billion, nine hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred ninety-eight".