12640144 has 30 divisors (see below), whose sum is σ = 26923190. Its totient is φ = 5744640.

The previous prime is 12640141. The next prime is 12640171. The reversal of 12640144 is 44104621.

It can be written as a sum of positive squares in only one way, i.e., 8179600 + 4460544 = 2860^2 + 2112^2 .

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12640141) 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 5 ways as a sum of consecutive naturals, for example, 1329 + ... + 5200.

Almost surely, 2^12640144 is an apocalyptic number.

It is an amenable number.

12640144 is an abundant number, since it is smaller than the sum of its proper divisors (14283046).

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

12640144 is a wasteful number, since it uses less digits than its factorization.

12640144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6559 (or 6542 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 22.

The square root of 12640144 is about 3555.2980184508. The cubic root of 12640144 is about 232.9435414914.

Adding to 12640144 its reverse (44104621), we get a palindrome (56744765).

The spelling of 12640144 in words is "twelve million, six hundred forty thousand, one hundred forty-four".