12221220221 has 8 divisors (see below), whose sum is σ = 13968362304. Its totient is φ = 10474391520.

The previous prime is 12221220173. The next prime is 12221220229. The reversal of 12221220221 is 12202212221.

It is a happy number.

12221220221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 12221220221 - 2¹⁴ = 12221203837 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 12221220221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12221220229) 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 7 ways as a sum of consecutive naturals, for example, 12206 + ... + 156816.

It is an arithmetic number, because the mean of its divisors is an integer number (1746045288).

Almost surely, 2^12221220221 is an apocalyptic number.

It is an amenable number.

12221220221 is a deficient number, since it is larger than the sum of its proper divisors (1747142083).

12221220221 is a wasteful number, since it uses less digits than its factorization.

12221220221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 156691.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 12221220221 its reverse (12202212221), we get a palindrome (24423432442).

The spelling of 12221220221 in words is "twelve billion, two hundred twenty-one million, two hundred twenty thousand, two hundred twenty-one".