1221200081191 has 2 divisors, whose sum is σ = 1221200081192. Its totient is φ = 1221200081190.

The previous prime is 1221200081149. The next prime is 1221200081201. The reversal of 1221200081191 is 1911800021221.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1221200081191 - 2³⁹ = 671444267303 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221200082191) 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, 610600040595 + 610600040596.

It is an arithmetic number, because the mean of its divisors is an integer number (610600040596).

Almost surely, 2^{1221200081191} is an apocalyptic number.

1221200081191 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221200081191 is an equidigital number, since it uses as much as digits as its factorization.

1221200081191 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 576, while the sum is 28.

The spelling of 1221200081191 in words is "one trillion, two hundred twenty-one billion, two hundred million, eighty-one thousand, one hundred ninety-one".