211112221021 has 4 divisors (see below), whose sum is σ = 227351622652. Its totient is φ = 194872819392.

The previous prime is 211112220989. The next prime is 211112221079. The reversal of 211112221021 is 120122211112.

211112221021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It can be written as a sum of positive squares in 2 ways, for example, as 141685240921 + 69426980100 = 376411^2 + 263490^2 .

It is a cyclic number.

It is not a de Polignac number, because 211112221021 - 2⁵ = 211112220989 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 211112220986 and 211112221004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211112221921) 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 3 ways as a sum of consecutive naturals, for example, 8119700796 + ... + 8119700821.

It is an arithmetic number, because the mean of its divisors is an integer number (56837905663).

Almost surely, 2^211112221021 is an apocalyptic number.

It is an amenable number.

211112221021 is a deficient number, since it is larger than the sum of its proper divisors (16239401631).

211112221021 is a wasteful number, since it uses less digits than its factorization.

211112221021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16239401630.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 211112221021 its reverse (120122211112), we get a palindrome (331234432133).

Subtracting from 211112221021 its reverse (120122211112), we obtain a palindrome (90990009909).

The spelling of 211112221021 in words is "two hundred eleven billion, one hundred twelve million, two hundred twenty-one thousand, twenty-one".