1221224221221 has 16 divisors (see below), whose sum is σ = 1676116464000. Its totient is φ = 790340977728.

The previous prime is 1221224221219. The next prime is 1221224221291.

1221224221221 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 1221224221221 - 2¹ = 1221224221219 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1221224221191 and 1221224221200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221224221291) 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, 12482046 + ... + 12579503.

It is an arithmetic number, because the mean of its divisors is an integer number (104757279000).

Almost surely, 2^{1221224221221} is an apocalyptic number.

It is an amenable number.

1221224221221 is a deficient number, since it is larger than the sum of its proper divisors (454892242779).

1221224221221 is a wasteful number, since it uses less digits than its factorization.

1221224221221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25062028.

The product of its digits is 1024, while the sum is 24.

The spelling of 1221224221221 in words is "one trillion, two hundred twenty-one billion, two hundred twenty-four million, two hundred twenty-one thousand, two hundred twenty-one".