20211111091 has 8 divisors (see below), whose sum is σ = 21285118800. Its totient is φ = 19138129920.

The previous prime is 20211111073. The next prime is 20211111203. The reversal of 20211111091 is 19011111202.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20211111091 - 2⁵ = 20211111059 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20211211091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 216046 + ... + 295123.

It is an arithmetic number, because the mean of its divisors is an integer number (2660639850).

Almost surely, 2^20211111091 is an apocalyptic number.

20211111091 is a deficient number, since it is larger than the sum of its proper divisors (1074007709).

20211111091 is a wasteful number, since it uses less digits than its factorization.

20211111091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 513269.

The product of its (nonzero) digits is 36, while the sum is 19.

Adding to 20211111091 its reverse (19011111202), we get a palindrome (39222222293).

It can be divided in two parts, 2021111 and 1091, that added together give a palindrome (2022202).

The spelling of 20211111091 in words is "twenty billion, two hundred eleven million, one hundred eleven thousand, ninety-one".