1221211102099 has 4 divisors (see below), whose sum is σ = 1236669470560. Its totient is φ = 1205752733640.

The previous prime is 1221211102081. The next prime is 1221211102121. The reversal of 1221211102099 is 9902011121221.

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 1221211102099 - 2³⁹ = 671455288211 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1221211102099.

It is not an unprimeable number, because it can be changed into a prime (1221211100099) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7729184112 + ... + 7729184269.

It is an arithmetic number, because the mean of its divisors is an integer number (309167367640).

Almost surely, 2^{1221211102099} is an apocalyptic number.

1221211102099 is a deficient number, since it is larger than the sum of its proper divisors (15458368461).

1221211102099 is an equidigital number, since it uses as much as digits as its factorization.

1221211102099 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15458368460.

The product of its (nonzero) digits is 1296, while the sum is 31.

The spelling of 1221211102099 in words is "one trillion, two hundred twenty-one billion, two hundred eleven million, one hundred two thousand, ninety-nine".