121220220991 has 2 divisors, whose sum is σ = 121220220992. Its totient is φ = 121220220990.

The previous prime is 121220220977. The next prime is 121220221021. The reversal of 121220220991 is 199022022121.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 121220220991 - 2²⁹ = 120683350079 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121220220911) 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, 60610110495 + 60610110496.

It is an arithmetic number, because the mean of its divisors is an integer number (60610110496).

Almost surely, 2^121220220991 is an apocalyptic number.

121220220991 is a deficient number, since it is larger than the sum of its proper divisors (1).

121220220991 is an equidigital number, since it uses as much as digits as its factorization.

121220220991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2592, while the sum is 31.

The spelling of 121220220991 in words is "one hundred twenty-one billion, two hundred twenty million, two hundred twenty thousand, nine hundred ninety-one".