122111221009991 has 2 divisors, whose sum is σ = 122111221009992. Its totient is φ = 122111221009990.

The previous prime is 122111221009913. The next prime is 122111221010011. The reversal of 122111221009991 is 199900122111221.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 122111221009991 - 2¹⁸ = 122111220747847 is a prime.

It is a super-2 number, since 2×122111221009991² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (122111221000991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61055610504995 + 61055610504996.

It is an arithmetic number, because the mean of its divisors is an integer number (61055610504996).

Almost surely, 2^{122111221009991} is an apocalyptic number.

122111221009991 is a deficient number, since it is larger than the sum of its proper divisors (1).

122111221009991 is an equidigital number, since it uses as much as digits as its factorization.

122111221009991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11664, while the sum is 41.

The spelling of 122111221009991 in words is "one hundred twenty-two trillion, one hundred eleven billion, two hundred twenty-one million, nine thousand, nine hundred ninety-one".