199911811 has 4 divisors (see below), whose sum is σ = 218085624. Its totient is φ = 181738000.

The previous prime is 199911799. The next prime is 199911847. The reversal of 199911811 is 118119991.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 118119991 = 11 ⋅10738181.

It is a cyclic number.

It is not a de Polignac number, because 199911811 - 2⁵ = 199911779 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (199911871) 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, 9086890 + ... + 9086911.

It is an arithmetic number, because the mean of its divisors is an integer number (54521406).

Almost surely, 2^199911811 is an apocalyptic number.

199911811 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

199911811 is a deficient number, since it is larger than the sum of its proper divisors (18173813).

199911811 is a wasteful number, since it uses less digits than its factorization.

199911811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18173812.

The product of its digits is 5832, while the sum is 40.

The square root of 199911811 is about 14139.0173279475. The cubic root of 199911811 is about 584.7175796055.

The spelling of 199911811 in words is "one hundred ninety-nine million, nine hundred eleven thousand, eight hundred eleven".