12222220221 has 16 divisors (see below), whose sum is σ = 18245219520. Its totient is φ = 8085944880.

The previous prime is 12222220207. The next prime is 12222220223. The reversal of 12222220221 is 12202222221.

12222220221 is a `hidden beast` number, since 1 + 2 + 222 + 220 + 221 = 666.

It is not a de Polignac number, because 12222220221 - 2¹⁷ = 12222089149 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12222220194 and 12222220203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12222220223) 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, 1724230 + ... + 1731303.

It is an arithmetic number, because the mean of its divisors is an integer number (1140326220).

Almost surely, 2^12222220221 is an apocalyptic number.

It is an amenable number.

12222220221 is a deficient number, since it is larger than the sum of its proper divisors (6022999299).

12222220221 is a wasteful number, since it uses less digits than its factorization.

12222220221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3455673 (or 3455667 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

Adding to 12222220221 its reverse (12202222221), we get a palindrome (24424442442).

The spelling of 12222220221 in words is "twelve billion, two hundred twenty-two million, two hundred twenty thousand, two hundred twenty-one".