12225440 has 48 divisors (see below), whose sum is σ = 29189160. Its totient is φ = 4838400.

The previous prime is 12225427. The next prime is 12225461. The reversal of 12225440 is 4452221.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 11916304 + 309136 = 3452^2 + 556^2 .

It is a super-2 number, since 2×12225440² = 298922766387200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 17090 + ... + 17790.

Almost surely, 2^12225440 is an apocalyptic number.

12225440 is a gapful number since it is divisible by the number (10) 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 12225440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14594580).

12225440 is an abundant number, since it is smaller than the sum of its proper divisors (16963720).

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

12225440 is a wasteful number, since it uses less digits than its factorization.

12225440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 825 (or 817 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 20.

The square root of 12225440 is about 3496.4896682244. The cubic root of 12225440 is about 230.3676539596.

Adding to 12225440 its reverse (4452221), we get a palindrome (16677661).

The spelling of 12225440 in words is "twelve million, two hundred twenty-five thousand, four hundred forty".