12222221 has 8 divisors (see below), whose sum is σ = 13392000. Its totient is φ = 11062240.

The previous prime is 12222211. The next prime is 12222241.

12222221 is nontrivially palindromic in base 10.

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 12222221 - 2¹⁰ = 12221197 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 12222196 and 12222205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12222211) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 305 + ... + 4953.

It is an arithmetic number, because the mean of its divisors is an integer number (1674000).

Almost surely, 2^12222221 is an apocalyptic number.

12222221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

12222221 is a deficient number, since it is larger than the sum of its proper divisors (1169779).

12222221 is a wasteful number, since it uses less digits than its factorization.

12222221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4899.

The product of its digits is 64, while the sum is 14.

The square root of 12222221 is about 3496.0293190990. The cubic root of 12222221 is about 230.3474333221.

It can be divided in two parts, 1222 and 2221, that added together give a palindrome (3443).

The spelling of 12222221 in words is "twelve million, two hundred twenty-two thousand, two hundred twenty-one".