121211022221 has 2 divisors, whose sum is σ = 121211022222. Its totient is φ = 121211022220.

The previous prime is 121211022203. The next prime is 121211022293. The reversal of 121211022221 is 122220112121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 98125562500 + 23085459721 = 313250^2 + 151939^2 .

It is a cyclic number.

It is not a de Polignac number, because 121211022221 - 2²⁶ = 121143913357 is a prime.

It is a super-2 number, since 2×121211022221² (a number of 23 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 121211022221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121211022521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60605511110 + 60605511111.

It is an arithmetic number, because the mean of its divisors is an integer number (60605511111).

Almost surely, 2^121211022221 is an apocalyptic number.

It is an amenable number.

121211022221 is a deficient number, since it is larger than the sum of its proper divisors (1).

121211022221 is an equidigital number, since it uses as much as digits as its factorization.

121211022221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 121211022221 its reverse (122220112121), we get a palindrome (243431134342).

The spelling of 121211022221 in words is "one hundred twenty-one billion, two hundred eleven million, twenty-two thousand, two hundred twenty-one".