13664728 has 48 divisors (see below), whose sum is σ = 32524200. Its totient is φ = 5322240.

The previous prime is 13664723. The next prime is 13664747. The reversal of 13664728 is 82746631.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13664723) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2728 + ... + 5896.

Almost surely, 2^13664728 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 13664728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16262100).

13664728 is an abundant number, since it is smaller than the sum of its proper divisors (18859472).

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

13664728 is a wasteful number, since it uses less digits than its factorization.

13664728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3200 (or 3189 counting only the distinct ones).

The product of its digits is 48384, while the sum is 37.

The square root of 13664728 is about 3696.5832873073. The cubic root of 13664728 is about 239.0747243923.

The spelling of 13664728 in words is "thirteen million, six hundred sixty-four thousand, seven hundred twenty-eight".