21222130121 has 2 divisors, whose sum is σ = 21222130122. Its totient is φ = 21222130120.

The previous prime is 21222130109. The next prime is 21222130141. The reversal of 21222130121 is 12103122212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13922820025 + 7299310096 = 117995^2 + 85436^2 .

It is a cyclic number.

It is not a de Polignac number, because 21222130121 - 2⁶ = 21222130057 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21222130121.

It is not a weakly prime, because it can be changed into another prime (21222130141) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10611065060 + 10611065061.

It is an arithmetic number, because the mean of its divisors is an integer number (10611065061).

Almost surely, 2^21222130121 is an apocalyptic number.

It is an amenable number.

21222130121 is a deficient number, since it is larger than the sum of its proper divisors (1).

21222130121 is an equidigital number, since it uses as much as digits as its factorization.

21222130121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 21222130121 its reverse (12103122212), we get a palindrome (33325252333).

The spelling of 21222130121 in words is "twenty-one billion, two hundred twenty-two million, one hundred thirty thousand, one hundred twenty-one".