20021100110191 has 4 divisors (see below), whose sum is σ = 20048046409872. Its totient is φ = 19994153810512.

The previous prime is 20021100110173. The next prime is 20021100110227. The reversal of 20021100110191 is 19101100112002.

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

It is a cyclic number.

It is not a de Polignac number, because 20021100110191 - 2¹⁵ = 20021100077423 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 (20021100110161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13473148726 + ... + 13473150211.

It is an arithmetic number, because the mean of its divisors is an integer number (5012011602468).

Almost surely, 2^{20021100110191} is an apocalyptic number.

20021100110191 is a deficient number, since it is larger than the sum of its proper divisors (26946299681).

20021100110191 is an equidigital number, since it uses as much as digits as its factorization.

20021100110191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26946299680.

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

Adding to 20021100110191 its reverse (19101100112002), we get a palindrome (39122200222193).

The spelling of 20021100110191 in words is "twenty trillion, twenty-one billion, one hundred million, one hundred ten thousand, one hundred ninety-one".