20011111191 has 12 divisors (see below), whose sum is σ = 29686153432. Its totient is φ = 12980180016.

The previous prime is 20011111157. The next prime is 20011111207. The reversal of 20011111191 is 19111111002.

It is not a de Polignac number, because 20011111191 - 2¹⁰ = 20011110167 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 (20011111151) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 30046381 + ... + 30047046.

Almost surely, 2^20011111191 is an apocalyptic number.

20011111191 is a deficient number, since it is larger than the sum of its proper divisors (9675042241).

20011111191 is a wasteful number, since it uses less digits than its factorization.

20011111191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60093470 (or 60093467 counting only the distinct ones).

The product of its (nonzero) digits is 18, while the sum is 18.

Adding to 20011111191 its reverse (19111111002), we get a palindrome (39122222193).

The spelling of 20011111191 in words is "twenty billion, eleven million, one hundred eleven thousand, one hundred ninety-one".