12212120121991 has 2 divisors, whose sum is σ = 12212120121992. Its totient is φ = 12212120121990.

The previous prime is 12212120121983. The next prime is 12212120122019. The reversal of 12212120121991 is 19912102121221.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 12212120121991 - 2³ = 12212120121983 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12212120121911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6106060060995 + 6106060060996.

It is an arithmetic number, because the mean of its divisors is an integer number (6106060060996).

Almost surely, 2^{12212120121991} is an apocalyptic number.

12212120121991 is a deficient number, since it is larger than the sum of its proper divisors (1).

12212120121991 is an equidigital number, since it uses as much as digits as its factorization.

12212120121991 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 34.

The spelling of 12212120121991 in words is "twelve trillion, two hundred twelve billion, one hundred twenty million, one hundred twenty-one thousand, nine hundred ninety-one".