1221123220113 has 16 divisors (see below), whose sum is σ = 1632633811200. Its totient is φ = 811848779280.

The previous prime is 1221123220111. The next prime is 1221123220139. The reversal of 1221123220113 is 3110223211221.

It is not a de Polignac number, because 1221123220113 - 2¹ = 1221123220111 is a prime.

It is a super-2 number, since 2×1221123220113² (a number of 25 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1221123220113.

It is not an unprimeable number, because it can be changed into a prime (1221123220111) 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, 3371178 + ... + 3715788.

It is an arithmetic number, because the mean of its divisors is an integer number (102039613200).

Almost surely, 2^{1221123220113} is an apocalyptic number.

It is an amenable number.

1221123220113 is a deficient number, since it is larger than the sum of its proper divisors (411510591087).

1221123220113 is a wasteful number, since it uses less digits than its factorization.

1221123220113 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 347852.

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

Adding to 1221123220113 its reverse (3110223211221), we get a palindrome (4331346431334).

The spelling of 1221123220113 in words is "one trillion, two hundred twenty-one billion, one hundred twenty-three million, two hundred twenty thousand, one hundred thirteen".