1221044423121 has 16 divisors (see below), whose sum is σ = 1809079245120. Its totient is φ = 813973570560.

The previous prime is 1221044423117. The next prime is 1221044423153. The reversal of 1221044423121 is 1213244401221.

1221044423121 is a `hidden beast` number, since 1 + 2 + 210 + 4 + 4 + 423 + 1 + 21 = 666.

It is not a de Polignac number, because 1221044423121 - 2² = 1221044423117 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (1221044423111) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1155495 + ... + 1943516.

It is an arithmetic number, because the mean of its divisors is an integer number (113067452820).

Almost surely, 2^{1221044423121} is an apocalyptic number.

It is an amenable number.

1221044423121 is a deficient number, since it is larger than the sum of its proper divisors (588034821999).

1221044423121 is a wasteful number, since it uses less digits than its factorization.

1221044423121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3113613 (or 3113607 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 27.

Adding to 1221044423121 its reverse (1213244401221), we get a palindrome (2434288824342).

The spelling of 1221044423121 in words is "one trillion, two hundred twenty-one billion, forty-four million, four hundred twenty-three thousand, one hundred twenty-one".