211111109999 has 4 divisors (see below), whose sum is σ = 220289853936. Its totient is φ = 201932366064.

The previous prime is 211111109977. The next prime is 211111110011. The reversal of 211111109999 is 999901111112.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-211111109999 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211111109939) 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, 4589371934 + ... + 4589371979.

It is an arithmetic number, because the mean of its divisors is an integer number (55072463484).

Almost surely, 2^211111109999 is an apocalyptic number.

211111109999 is a deficient number, since it is larger than the sum of its proper divisors (9178743937).

211111109999 is an equidigital number, since it uses as much as digits as its factorization.

211111109999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9178743936.

The product of its (nonzero) digits is 13122, while the sum is 44.

The spelling of 211111109999 in words is "two hundred eleven billion, one hundred eleven million, one hundred nine thousand, nine hundred ninety-nine".