12222122121221 has 2 divisors, whose sum is σ = 12222122121222. Its totient is φ = 12222122121220.

The previous prime is 12222122121217. The next prime is 12222122121229. The reversal of 12222122121221 is 12212122122221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12222120880225 + 1240996 = 3496015^2 + 1114^2 .

It is a cyclic number.

It is not a de Polignac number, because 12222122121221 - 2² = 12222122121217 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12222122121229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6111061060610 + 6111061060611.

It is an arithmetic number, because the mean of its divisors is an integer number (6111061060611).

Almost surely, 2^{12222122121221} is an apocalyptic number.

It is an amenable number.

12222122121221 is a deficient number, since it is larger than the sum of its proper divisors (1).

12222122121221 is an equidigital number, since it uses as much as digits as its factorization.

12222122121221 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 12222122121221 its reverse (12212122122221), we get a palindrome (24434244243442).

It can be divided in two parts, 1222212 and 2121221, that added together give a palindrome (3343433).

The spelling of 12222122121221 in words is "twelve trillion, two hundred twenty-two billion, one hundred twenty-two million, one hundred twenty-one thousand, two hundred twenty-one".