121222122221 has 2 divisors, whose sum is σ = 121222122222. Its totient is φ = 121222122220.

The previous prime is 121222122187. The next prime is 121222122223. The reversal of 121222122221 is 122221222121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 61839255625 + 59382866596 = 248675^2 + 243686^2 .

It is a cyclic number.

It is not a de Polignac number, because 121222122221 - 2³⁰ = 120148380397 is a prime.

Together with 121222122223, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 121222122193 and 121222122202.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121222122223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60611061110 + 60611061111.

It is an arithmetic number, because the mean of its divisors is an integer number (60611061111).

Almost surely, 2^121222122221 is an apocalyptic number.

It is an amenable number.

121222122221 is a deficient number, since it is larger than the sum of its proper divisors (1).

121222122221 is an equidigital number, since it uses as much as digits as its factorization.

121222122221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 256, while the sum is 20.

Adding to 121222122221 its reverse (122221222121), we get a palindrome (243443344342).

The spelling of 121222122221 in words is "one hundred twenty-one billion, two hundred twenty-two million, one hundred twenty-two thousand, two hundred twenty-one".