20191109191 has 12 divisors (see below), whose sum is σ = 22212641752. Its totient is φ = 18339750000.

The previous prime is 20191109179. The next prime is 20191109209. The reversal of 20191109191 is 19190119102.

It is not a de Polignac number, because 20191109191 - 2¹¹ = 20191107143 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 (20191109101) 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 11 ways as a sum of consecutive naturals, for example, 70441 + ... + 212941.

Almost surely, 2^20191109191 is an apocalyptic number.

20191109191 is a deficient number, since it is larger than the sum of its proper divisors (2021532561).

20191109191 is a wasteful number, since it uses less digits than its factorization.

20191109191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143694 (or 143683 counting only the distinct ones).

The product of its (nonzero) digits is 1458, while the sum is 34.

The spelling of 20191109191 in words is "twenty billion, one hundred ninety-one million, one hundred nine thousand, one hundred ninety-one".