12216644 has 36 divisors (see below), whose sum is σ = 24086832. Its totient is φ = 5414640.

The previous prime is 12216643. The next prime is 12216661. The reversal of 12216644 is 44661221.

It is not an unprimeable number, because it can be changed into a prime (12216643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 20519 + ... + 21105.

Almost surely, 2^12216644 is an apocalyptic number.

It is an amenable number.

12216644 is a deficient number, since it is larger than the sum of its proper divisors (11870188).

12216644 is a wasteful number, since it uses less digits than its factorization.

12216644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 656 (or 643 counting only the distinct ones).

The product of its digits is 2304, while the sum is 26.

The square root of 12216644 is about 3495.2316089209. The cubic root of 12216644 is about 230.3123921437.

Adding to 12216644 its reverse (44661221), we get a palindrome (56877865).

The spelling of 12216644 in words is "twelve million, two hundred sixteen thousand, six hundred forty-four".