198999011111111 has 4 divisors (see below), whose sum is σ = 198999054358800. Its totient is φ = 198998967863424.

The previous prime is 198999011111099. The next prime is 198999011111143. The reversal of 198999011111111 is 111111110999891.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 198999011111111 - 2¹⁴ = 198999011094727 is a prime.

It is a Duffinian number.

198999011111111 is a modest number, since divided by 11111111 gives 1989990 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (198999011111191) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13771226 + ... + 24241383.

It is an arithmetic number, because the mean of its divisors is an integer number (49749763589700).

Almost surely, 2^{198999011111111} is an apocalyptic number.

198999011111111 is a deficient number, since it is larger than the sum of its proper divisors (43247689).

198999011111111 is an equidigital number, since it uses as much as digits as its factorization.

198999011111111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43247688.

The product of its (nonzero) digits is 52488, while the sum is 53.

It can be divided in two parts, 19899901 and 1111111, that added together give a palindrome (21011012).

The spelling of 198999011111111 in words is "one hundred ninety-eight trillion, nine hundred ninety-nine billion, eleven million, one hundred eleven thousand, one hundred eleven".