1221211121199 has 4 divisors (see below), whose sum is σ = 1628281494936. Its totient is φ = 814140747464.

The previous prime is 1221211121177. The next prime is 1221211121269. The reversal of 1221211121199 is 9911211121221.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1221211121199 - 2¹⁵ = 1221211088431 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221211121099) 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 in 3 ways as a sum of consecutive naturals, for example, 203535186864 + ... + 203535186869.

It is an arithmetic number, because the mean of its divisors is an integer number (407070373734).

Almost surely, 2^{1221211121199} is an apocalyptic number.

1221211121199 is a deficient number, since it is larger than the sum of its proper divisors (407070373737).

1221211121199 is an equidigital number, since it uses as much as digits as its factorization.

1221211121199 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 407070373736.

The product of its digits is 1296, while the sum is 33.

The spelling of 1221211121199 in words is "one trillion, two hundred twenty-one billion, two hundred eleven million, one hundred twenty-one thousand, one hundred ninety-nine".