21222120210221 has 16 divisors (see below), whose sum is σ = 24711719760000. Its totient is φ = 17846994579648.

The previous prime is 21222120210217. The next prime is 21222120210271. The reversal of 21222120210221 is 12201202122212.

It is a cyclic number.

It is not a de Polignac number, because 21222120210221 - 2² = 21222120210217 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21222120210193 and 21222120210202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21222120210271) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 47301455 + ... + 47748003.

It is an arithmetic number, because the mean of its divisors is an integer number (1544482485000).

Almost surely, 2^{21222120210221} is an apocalyptic number.

It is an amenable number.

21222120210221 is a deficient number, since it is larger than the sum of its proper divisors (3489599549779).

21222120210221 is a wasteful number, since it uses less digits than its factorization.

21222120210221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 574708.

The product of its (nonzero) digits is 256, while the sum is 20.

Adding to 21222120210221 its reverse (12201202122212), we get a palindrome (33423322332433).

The spelling of 21222120210221 in words is "twenty-one trillion, two hundred twenty-two billion, one hundred twenty million, two hundred ten thousand, two hundred twenty-one".