12220128 has 72 divisors (see below), whose sum is σ = 35105616. Its totient is φ = 4032000.

The previous prime is 12220111. The next prime is 12220129. The reversal of 12220128 is 82102221.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a self number, because there is not a number n which added to its sum of digits gives 12220128.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12220129) 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 11 ways as a sum of consecutive naturals, for example, 43348 + ... + 43628.

It is an arithmetic number, because the mean of its divisors is an integer number (487578).

Almost surely, 2^12220128 is an apocalyptic number.

12220128 is a gapful number since it is divisible by the number (18) 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 12220128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17552808).

12220128 is an abundant number, since it is smaller than the sum of its proper divisors (22885488).

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

12220128 is a wasteful number, since it uses less digits than its factorization.

12220128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 448 (or 437 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

The square root of 12220128 is about 3495.7299666879. The cubic root of 12220128 is about 230.3342839199.

Adding to 12220128 its reverse (82102221), we get a palindrome (94322349).

The spelling of 12220128 in words is "twelve million, two hundred twenty thousand, one hundred twenty-eight".