12281640 has 64 divisors (see below), whose sum is σ = 42111360. Its totient is φ = 2807040.

The previous prime is 12281603. The next prime is 12281641. The reversal of 12281640 is 4618221.

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

It is a self number, because there is not a number n which added to its sum of digits gives 12281640.

It is not an unprimeable number, because it can be changed into a prime (12281641) 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, 6471 + ... + 8150.

It is an arithmetic number, because the mean of its divisors is an integer number (657990).

Almost surely, 2^12281640 is an apocalyptic number.

12281640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12281640 is an abundant number, since it is smaller than the sum of its proper divisors (29829720).

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

12281640 is a wasteful number, since it uses less digits than its factorization.

12281640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14642 (or 14638 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 24.

The square root of 12281640 is about 3504.5170851346. The cubic root of 12281640 is about 230.7201122811.

Adding to 12281640 its reverse (4618221), we get a palindrome (16899861).

It can be divided in two parts, 12281 and 640, that added together give a palindrome (12921).

The spelling of 12281640 in words is "twelve million, two hundred eighty-one thousand, six hundred forty".