12320640 has 256 divisors, whose sum is σ = 47001600. Its totient is φ = 3041280.

The previous prime is 12320599. The next prime is 12320647. The reversal of 12320640 is 4602321.

It is a happy number.

12320640 is a `hidden beast` number, since 1 + 2 + 3 + 20 + 640 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12320647) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 397425 + ... + 397455.

It is an arithmetic number, because the mean of its divisors is an integer number (183600).

Almost surely, 2^12320640 is an apocalyptic number.

12320640 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 12320640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23500800).

12320640 is an abundant number, since it is smaller than the sum of its proper divisors (34680960).

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

12320640 is a wasteful number, since it uses less digits than its factorization.

12320640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82 (or 64 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 12320640 is about 3510.0769222340. The cubic root of 12320640 is about 230.9640692976.

Adding to 12320640 its reverse (4602321), we get a palindrome (16922961).

The spelling of 12320640 in words is "twelve million, three hundred twenty thousand, six hundred forty".