21112112110221 has 24 divisors (see below), whose sum is σ = 33267943328256. Its totient is φ = 12795076103040.

The previous prime is 21112112110217. The next prime is 21112112110249. The reversal of 21112112110221 is 12201121121112.

It is a happy number.

21112112110221 is a `hidden beast` number, since 21 + 1 + 1 + 211 + 211 + 0 + 221 = 666.

It is not a de Polignac number, because 21112112110221 - 2² = 21112112110217 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21112112110194 and 21112112110203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21112112110321) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8045221 + ... + 10341653.

It is an arithmetic number, because the mean of its divisors is an integer number (1386164305344).

Almost surely, 2^{21112112110221} is an apocalyptic number.

It is an amenable number.

21112112110221 is a deficient number, since it is larger than the sum of its proper divisors (12155831218035).

21112112110221 is a wasteful number, since it uses less digits than its factorization.

21112112110221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2389313 (or 2389310 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 18.

Adding to 21112112110221 its reverse (12201121121112), we get a palindrome (33313233231333).

The spelling of 21112112110221 in words is "twenty-one trillion, one hundred twelve billion, one hundred twelve million, one hundred ten thousand, two hundred twenty-one".