13663999 has 2 divisors, whose sum is σ = 13664000. Its totient is φ = 13663998.

The previous prime is 13663997. The next prime is 13664069. The reversal of 13663999 is 99936631.

It is a weak prime.

It is an emirp because it is prime and its reverse (99936631) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 13663999 - 2¹ = 13663997 is a prime.

Together with 13663997, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13663997) 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 as a sum of consecutive naturals, namely, 6831999 + 6832000.

It is an arithmetic number, because the mean of its divisors is an integer number (6832000).

Almost surely, 2^13663999 is an apocalyptic number.

13663999 is a deficient number, since it is larger than the sum of its proper divisors (1).

13663999 is an equidigital number, since it uses as much as digits as its factorization.

13663999 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 236196, while the sum is 46.

The square root of 13663999 is about 3696.4846814237. The cubic root of 13663999 is about 239.0704728484.

The spelling of 13663999 in words is "thirteen million, six hundred sixty-three thousand, nine hundred ninety-nine".