13666687 has 2 divisors, whose sum is σ = 13666688. Its totient is φ = 13666686.

The previous prime is 13666673. The next prime is 13666711. The reversal of 13666687 is 78666631.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13666687 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13666607) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6833343 + 6833344.

It is an arithmetic number, because the mean of its divisors is an integer number (6833344).

Almost surely, 2^13666687 is an apocalyptic number.

13666687 is a deficient number, since it is larger than the sum of its proper divisors (1).

13666687 is an equidigital number, since it uses as much as digits as its factorization.

13666687 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 217728, while the sum is 43.

The square root of 13666687 is about 3696.8482522278. The cubic root of 13666687 is about 239.0861485740.

The spelling of 13666687 in words is "thirteen million, six hundred sixty-six thousand, six hundred eighty-seven".