21222044214121 has 9 divisors (see below), whose sum is σ = 22184969837079. Its totient is φ = 20299245291336.

The previous prime is 21222044214109. The next prime is 21222044214127. The reversal of 21222044214121 is 12141244022212.

The square root of 21222044214121 is 4606739.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 21017411025625 + 204633188496 = 4584475^2 + 452364^2 .

It is not a de Polignac number, because 21222044214121 - 2¹⁵ = 21222044181353 is a prime.

It is a super-2 number, since 2×21222044214121² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21222044214121.

It is not an unprimeable number, because it can be changed into a prime (21222044214127) 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 8 ways as a sum of consecutive naturals, for example, 105854851 + ... + 106055143.

Almost surely, 2^{21222044214121} is an apocalyptic number.

21222044214121 is the 4606739-th square number.

21222044214121 is the 2303370-th centered octagonal number.

It is an amenable number.

21222044214121 is a deficient number, since it is larger than the sum of its proper divisors (962925622958).

21222044214121 is an frugal number, since it uses more digits than its factorization.

21222044214121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 400632 (or 200316 counting only the distinct ones).

The product of its (nonzero) digits is 4096, while the sum is 28.

Adding to 21222044214121 its reverse (12141244022212), we get a palindrome (33363288236333).

The spelling of 21222044214121 in words is "twenty-one trillion, two hundred twenty-two billion, forty-four million, two hundred fourteen thousand, one hundred twenty-one".