13688729 has 4 divisors (see below), whose sum is σ = 13881600. Its totient is φ = 13495860.

The previous prime is 13688699. The next prime is 13688761. The reversal of 13688729 is 92788631.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 92788631 = 13 ⋅7137587.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13688729 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 13688729.

It is not an unprimeable number, because it can be changed into a prime (13688789) 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, 96329 + ... + 96470.

It is an arithmetic number, because the mean of its divisors is an integer number (3470400).

Almost surely, 2^13688729 is an apocalyptic number.

It is an amenable number.

13688729 is a deficient number, since it is larger than the sum of its proper divisors (192871).

13688729 is an equidigital number, since it uses as much as digits as its factorization.

13688729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 192870.

The product of its digits is 145152, while the sum is 44.

The square root of 13688729 is about 3699.8282392565. The cubic root of 13688729 is about 239.2146143892.

The spelling of 13688729 in words is "thirteen million, six hundred eighty-eight thousand, seven hundred twenty-nine".