12221664 has 96 divisors (see below), whose sum is σ = 39513600. Its totient is φ = 3220992.

The previous prime is 12221611. The next prime is 12221669. The reversal of 12221664 is 46612221.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12221669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8037 + ... + 9435.

It is an arithmetic number, because the mean of its divisors is an integer number (411600).

Almost surely, 2^12221664 is an apocalyptic number.

12221664 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12221664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19756800).

12221664 is an abundant number, since it is smaller than the sum of its proper divisors (27291936).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

12221664 is a wasteful number, since it uses less digits than its factorization.

12221664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1432 (or 1424 counting only the distinct ones).

The product of its digits is 1152, while the sum is 24.

The square root of 12221664 is about 3495.9496563881. The cubic root of 12221664 is about 230.3439340817.

Adding to 12221664 its reverse (46612221), we get a palindrome (58833885).

The spelling of 12221664 in words is "twelve million, two hundred twenty-one thousand, six hundred sixty-four".