13809728 has 28 divisors (see below), whose sum is σ = 27992832. Its totient is φ = 6756480.

The previous prime is 13809709. The next prime is 13809749. The reversal of 13809728 is 82790831.

It is a junction number, because it is equal to n+sod(n) for n = 13809691 and 13809700.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 713 + ... + 5303.

It is an arithmetic number, because the mean of its divisors is an integer number (999744).

Almost surely, 2^13809728 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 13809728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13996416).

13809728 is an abundant number, since it is smaller than the sum of its proper divisors (14183104).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

13809728 is an equidigital number, since it uses as much as digits as its factorization.

13809728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4650 (or 4640 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 38.

The square root of 13809728 is about 3716.1442383201. The cubic root of 13809728 is about 239.9173789680.

The spelling of 13809728 in words is "thirteen million, eight hundred nine thousand, seven hundred twenty-eight".