12212221221 has 24 divisors (see below), whose sum is σ = 18211574784. Its totient is φ = 7879926240.

The previous prime is 12212221213. The next prime is 12212221247.

It is a happy number.

12212221221 is a `hidden beast` number, since 1 + 221 + 2 + 221 + 221 = 666.

12212221221 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 12212221221 - 2³ = 12212221213 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 12212221194 and 12212221203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12212221261) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 32401 + ... + 159606.

It is an arithmetic number, because the mean of its divisors is an integer number (758815616).

Almost surely, 2^12212221221 is an apocalyptic number.

It is an amenable number.

12212221221 is a deficient number, since it is larger than the sum of its proper divisors (5999353563).

12212221221 is a wasteful number, since it uses less digits than its factorization.

12212221221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 192241 (or 192238 counting only the distinct ones).

The product of its digits is 128, while the sum is 18.

The spelling of 12212221221 in words is "twelve billion, two hundred twelve million, two hundred twenty-one thousand, two hundred twenty-one".