199998899991 has 72 divisors (see below), whose sum is σ = 326502146880. Its totient is φ = 117811584000.

The previous prime is 199998899963. The next prime is 199998900001.

199998899991 is nontrivially palindromic in base 10.

199998899991 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 199998899991 - 2⁹ = 199998899479 is a prime.

It is a super-2 number, since 2×199998899991² (a number of 23 digits) contains 22 as substring.

199998899991 is a modest number, since divided by 899991 gives 199998 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (199998899911) 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 71 ways as a sum of consecutive naturals, for example, 12091615 + ... + 12108143.

It is an arithmetic number, because the mean of its divisors is an integer number (4534752040).

Almost surely, 2^199998899991 is an apocalyptic number.

199998899991 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

199998899991 is a deficient number, since it is larger than the sum of its proper divisors (126503246889).

199998899991 is a wasteful number, since it uses less digits than its factorization.

199998899991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16869 (or 16855 counting only the distinct ones).

The product of its digits is 2754990144, while the sum is 90.

The spelling of 199998899991 in words is "one hundred ninety-nine billion, nine hundred ninety-eight million, eight hundred ninety-nine thousand, nine hundred ninety-one".