12686643 has 12 divisors (see below), whose sum is σ = 18359328. Its totient is φ = 8442000.

The previous prime is 12686629. The next prime is 12686647. The reversal of 12686643 is 34668621.

12686643 is a `hidden beast` number, since 1 + 2 + 6 + 8 + 6 + 643 = 666.

It is not a de Polignac number, because 12686643 - 2⁴ = 12686627 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12686598 and 12686607.

It is not an unprimeable number, because it can be changed into a prime (12686647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5821 + ... + 7697.

It is an arithmetic number, because the mean of its divisors is an integer number (1529944).

Almost surely, 2^12686643 is an apocalyptic number.

12686643 is the 2253-rd heptagonal number.

12686643 is a deficient number, since it is larger than the sum of its proper divisors (5672685).

12686643 is a wasteful number, since it uses less digits than its factorization.

12686643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2634 (or 2631 counting only the distinct ones).

The product of its digits is 41472, while the sum is 36.

The square root of 12686643 is about 3561.8314109458. The cubic root of 12686643 is about 233.2288332512.

The spelling of 12686643 in words is "twelve million, six hundred eighty-six thousand, six hundred forty-three".