13247999 has 4 divisors (see below), whose sum is σ = 13556136. Its totient is φ = 12939864.

The previous prime is 13247989. The next prime is 13248017. The reversal of 13247999 is 99974231.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13247999 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13247939) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 154004 + ... + 154089.

It is an arithmetic number, because the mean of its divisors is an integer number (3389034).

Almost surely, 2^13247999 is an apocalyptic number.

13247999 is a deficient number, since it is larger than the sum of its proper divisors (308137).

13247999 is an equidigital number, since it uses as much as digits as its factorization.

13247999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 308136.

The product of its digits is 122472, while the sum is 44.

The square root of 13247999 is about 3639.7800757738. The cubic root of 13247999 is about 236.6192620344.

The spelling of 13247999 in words is "thirteen million, two hundred forty-seven thousand, nine hundred ninety-nine".