12640109940 has 240 divisors, whose sum is σ = 41400208080. Its totient is φ = 3224309760.

The previous prime is 12640109939. The next prime is 12640109947. The reversal of 12640109940 is 4990104621.

It is a happy number.

12640109940 is a `hidden beast` number, since 1 + 2 + 640 + 1 + 0 + 9 + 9 + 4 + 0 = 666.

12640109940 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 8 ways, for example, as 6038222436 + 6601887504 = 77706^2 + 81252^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 12640109895 and 12640109904.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12640109947) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 5307550 + ... + 5309930.

It is an arithmetic number, because the mean of its divisors is an integer number (172500867).

Almost surely, 2^12640109940 is an apocalyptic number.

12640109940 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 12640109940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20700104040).

12640109940 is an abundant number, since it is smaller than the sum of its proper divisors (28760098140).

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

12640109940 is a wasteful number, since it uses less digits than its factorization.

12640109940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2544 (or 2533 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The spelling of 12640109940 in words is "twelve billion, six hundred forty million, one hundred nine thousand, nine hundred forty".