20211111021111 has 4 divisors (see below), whose sum is σ = 26948148028152. Its totient is φ = 13474074014072.

The previous prime is 20211111021067. The next prime is 20211111021121. The reversal of 20211111021111 is 11112011111202.

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 20211111021111 - 2⁹ = 20211111020599 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20211111021121) 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, 3368518503516 + ... + 3368518503521.

It is an arithmetic number, because the mean of its divisors is an integer number (6737037007038).

Almost surely, 2^{20211111021111} is an apocalyptic number.

20211111021111 is a deficient number, since it is larger than the sum of its proper divisors (6737037007041).

20211111021111 is an equidigital number, since it uses as much as digits as its factorization.

20211111021111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6737037007040.

The product of its (nonzero) digits is 8, while the sum is 15.

Adding to 20211111021111 its reverse (11112011111202), we get a palindrome (31323122132313).

Subtracting from 20211111021111 its reverse (11112011111202), we obtain a palindrome (9099099909909).

The spelling of 20211111021111 in words is "twenty trillion, two hundred eleven billion, one hundred eleven million, twenty-one thousand, one hundred eleven".