21112222222221 has 8 divisors (see below), whose sum is σ = 30314985755040. Its totient is φ = 12992136752112.

The previous prime is 21112222222219. The next prime is 21112222222309. The reversal of 21112222222221 is 12222222221112.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21112222222221 - 2¹ = 21112222222219 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21112222222191 and 21112222222200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21112222222211) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 270669515631 + ... + 270669515708.

It is an arithmetic number, because the mean of its divisors is an integer number (3789373219380).

Almost surely, 2^{21112222222221} is an apocalyptic number.

It is an amenable number.

21112222222221 is a deficient number, since it is larger than the sum of its proper divisors (9202763532819).

21112222222221 is a wasteful number, since it uses less digits than its factorization.

21112222222221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 541339031355.

The product of its digits is 1024, while the sum is 24.

Adding to 21112222222221 its reverse (12222222221112), we get a palindrome (33334444443333).

The spelling of 21112222222221 in words is "twenty-one trillion, one hundred twelve billion, two hundred twenty-two million, two hundred twenty-two thousand, two hundred twenty-one".