12005640 has 48 divisors (see below), whose sum is σ = 39019500. Its totient is φ = 3201408.

The previous prime is 12005629. The next prime is 12005641. The reversal of 12005640 is 4650021.

It is a happy number.

12005640 is a `hidden beast` number, since 1 + 20 + 0 + 5 + 640 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 11329956 + 675684 = 3366^2 + 822^2 .

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

It is not an unprimeable number, because it can be changed into a prime (12005641) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16315 + ... + 17034.

Almost surely, 2^12005640 is an apocalyptic number.

12005640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12005640 is an abundant number, since it is smaller than the sum of its proper divisors (27013860).

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

12005640 is a wasteful number, since it uses less digits than its factorization.

12005640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33366 (or 33359 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 12005640 is about 3464.9155833873. The cubic root of 12005640 is about 228.9787106058.

Adding to 12005640 its reverse (4650021), we get a palindrome (16655661).

The spelling of 12005640 in words is "twelve million, five thousand, six hundred forty".