12640442136 has 64 divisors (see below), whose sum is σ = 36169536000. Its totient is φ = 3606156288.

The previous prime is 12640442069. The next prime is 12640442161. The reversal of 12640442136 is 63124404621.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 12640442097 and 12640442106.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 57165 + ... + 168963.

It is an arithmetic number, because the mean of its divisors is an integer number (565149000).

Almost surely, 2^12640442136 is an apocalyptic number.

It is an amenable number.

12640442136 is an abundant number, since it is smaller than the sum of its proper divisors (23529093864).

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

12640442136 is a wasteful number, since it uses less digits than its factorization.

12640442136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112488 (or 112484 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 33.

Adding to 12640442136 its reverse (63124404621), we get a palindrome (75764846757).

The spelling of 12640442136 in words is "twelve billion, six hundred forty million, four hundred forty-two thousand, one hundred thirty-six".