22122121122221 has 2 divisors, whose sum is σ = 22122121122222. Its totient is φ = 22122121122220.

The previous prime is 22122121122191. The next prime is 22122121122229. The reversal of 22122121122221 is 12222112122122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16341919440196 + 5780201682025 = 4042514^2 + 2404205^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-22122121122221 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (22122121122229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11061060561110 + 11061060561111.

It is an arithmetic number, because the mean of its divisors is an integer number (11061060561111).

Almost surely, 2^{22122121122221} is an apocalyptic number.

It is an amenable number.

22122121122221 is a deficient number, since it is larger than the sum of its proper divisors (1).

22122121122221 is an equidigital number, since it uses as much as digits as its factorization.

22122121122221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 512, while the sum is 23.

Adding to 22122121122221 its reverse (12222112122122), we get a palindrome (34344233244343).

Subtracting from 22122121122221 its reverse (12222112122122), we obtain a palindrome (9900009000099).

The spelling of 22122121122221 in words is "twenty-two trillion, one hundred twenty-two billion, one hundred twenty-one million, one hundred twenty-two thousand, two hundred twenty-one".