121222220221 has 2 divisors, whose sum is σ = 121222220222. Its totient is φ = 121222220220.

The previous prime is 121222220183. The next prime is 121222220227. The reversal of 121222220221 is 122022222121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 62430519321 + 58791700900 = 249861^2 + 242470^2 .

It is a cyclic number.

It is not a de Polignac number, because 121222220221 - 2²⁷ = 121088002493 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121222220227) 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 as a sum of consecutive naturals, namely, 60611110110 + 60611110111.

It is an arithmetic number, because the mean of its divisors is an integer number (60611110111).

Almost surely, 2^121222220221 is an apocalyptic number.

It is an amenable number.

121222220221 is a deficient number, since it is larger than the sum of its proper divisors (1).

121222220221 is an equidigital number, since it uses as much as digits as its factorization.

121222220221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 256, while the sum is 19.

Adding to 121222220221 its reverse (122022222121), we get a palindrome (243244442342).

The spelling of 121222220221 in words is "one hundred twenty-one billion, two hundred twenty-two million, two hundred twenty thousand, two hundred twenty-one".