12220221 has 12 divisors (see below), whose sum is σ = 17644128. Its totient is φ = 7519824.

The previous prime is 12220217. The next prime is 12220237. The reversal of 12220221 is 12202221.

It is not a de Polignac number, because 12220221 - 2² = 12220217 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12220197 and 12220206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12220261) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11545 + ... + 12558.

It is an arithmetic number, because the mean of its divisors is an integer number (1470344).

Almost surely, 2^12220221 is an apocalyptic number.

It is an amenable number.

12220221 is a deficient number, since it is larger than the sum of its proper divisors (5423907).

12220221 is a wasteful number, since it uses less digits than its factorization.

12220221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24132 (or 24119 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 12.

The square root of 12220221 is about 3495.7432686054. The cubic root of 12220221 is about 230.3348682300.

Adding to 12220221 its reverse (12202221), we get a palindrome (24422442).

It can be divided in two parts, 1 and 2220221, that added together give a palindrome (2220222).

The spelling of 12220221 in words is "twelve million, two hundred twenty thousand, two hundred twenty-one".