12001222221 has 24 divisors (see below), whose sum is σ = 16634985120. Its totient is φ = 7695772224.

The previous prime is 12001222193. The next prime is 12001222223. The reversal of 12001222221 is 12222210021.

12001222221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 12001222221 - 2¹⁴ = 12001205837 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 12001222221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12001222223) 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 23 ways as a sum of consecutive naturals, for example, 669846 + ... + 687528.

It is an arithmetic number, because the mean of its divisors is an integer number (693124380).

Almost surely, 2^12001222221 is an apocalyptic number.

It is an amenable number.

12001222221 is a deficient number, since it is larger than the sum of its proper divisors (4633762899).

12001222221 is a wasteful number, since it uses less digits than its factorization.

12001222221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18013 (or 17984 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 12001222221 its reverse (12222210021), we get a palindrome (24223432242).

The spelling of 12001222221 in words is "twelve billion, one million, two hundred twenty-two thousand, two hundred twenty-one".