1221203112213 has 16 divisors (see below), whose sum is σ = 1970344517760. Its totient is φ = 656781505536.

The previous prime is 1221203112169. The next prime is 1221203112229. The reversal of 1221203112213 is 3122113021221.

It is not a de Polignac number, because 1221203112213 - 2²⁵ = 1221169557781 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a self number, because there is not a number n which added to its sum of digits gives 1221203112213.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221203112113) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1710368148 + ... + 1710368861.

It is an arithmetic number, because the mean of its divisors is an integer number (123146532360).

Almost surely, 2^{1221203112213} is an apocalyptic number.

It is an amenable number.

1221203112213 is a deficient number, since it is larger than the sum of its proper divisors (749141405547).

1221203112213 is a wasteful number, since it uses less digits than its factorization.

1221203112213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3420737036.

The product of its (nonzero) digits is 288, while the sum is 21.

Adding to 1221203112213 its reverse (3122113021221), we get a palindrome (4343316133434).

The spelling of 1221203112213 in words is "one trillion, two hundred twenty-one billion, two hundred three million, one hundred twelve thousand, two hundred thirteen".