21112202221111 has 4 divisors (see below), whose sum is σ = 21112211478312. Its totient is φ = 21112192963912.

The previous prime is 21112202221093. The next prime is 21112202221139. The reversal of 21112202221111 is 11112220221112.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 21112202221111 - 2⁷ = 21112202220983 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 (21112202221141) 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, 1476801 + ... + 6663733.

It is an arithmetic number, because the mean of its divisors is an integer number (5278052869578).

Almost surely, 2^{21112202221111} is an apocalyptic number.

21112202221111 is a deficient number, since it is larger than the sum of its proper divisors (9257201).

21112202221111 is an equidigital number, since it uses as much as digits as its factorization.

21112202221111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9257200.

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 21112202221111 its reverse (11112220221112), we get a palindrome (32224422442223).

The spelling of 21112202221111 in words is "twenty-one trillion, one hundred twelve billion, two hundred two million, two hundred twenty-one thousand, one hundred eleven".