21222001214221 has 2 divisors, whose sum is σ = 21222001214222. Its totient is φ = 21222001214220.

The previous prime is 21222001214201. The next prime is 21222001214257. The reversal of 21222001214221 is 12241210022212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15804488936196 + 5417512278025 = 3975486^2 + 2327555^2 .

It is a cyclic number.

It is not a de Polignac number, because 21222001214221 - 2⁷ = 21222001214093 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21222001214192 and 21222001214201.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21222001214201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10611000607110 + 10611000607111.

It is an arithmetic number, because the mean of its divisors is an integer number (10611000607111).

Almost surely, 2^{21222001214221} is an apocalyptic number.

It is an amenable number.

21222001214221 is a deficient number, since it is larger than the sum of its proper divisors (1).

21222001214221 is an equidigital number, since it uses as much as digits as its factorization.

21222001214221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 512, while the sum is 22.

Adding to 21222001214221 its reverse (12241210022212), we get a palindrome (33463211236433).

The spelling of 21222001214221 in words is "twenty-one trillion, two hundred twenty-two billion, one million, two hundred fourteen thousand, two hundred twenty-one".