12643999478 has 16 divisors (see below), whose sum is σ = 21403636560. Its totient is φ = 5549090400.

The previous prime is 12643999463. The next prime is 12643999523. The reversal of 12643999478 is 87499934621.

It is a self number, because there is not a number n which added to its sum of digits gives 12643999478.

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 7 ways as a sum of consecutive naturals, for example, 9908453 + ... + 9909728.

It is an arithmetic number, because the mean of its divisors is an integer number (1337727285).

Almost surely, 2^12643999478 is an apocalyptic number.

12643999478 is a deficient number, since it is larger than the sum of its proper divisors (8759637082).

12643999478 is a wasteful number, since it uses less digits than its factorization.

12643999478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19818223.

The product of its digits is 23514624, while the sum is 62.

The spelling of 12643999478 in words is "twelve billion, six hundred forty-three million, nine hundred ninety-nine thousand, four hundred seventy-eight".