18809728 has 48 divisors (see below), whose sum is σ = 43605000. Its totient is φ = 8058624.

The previous prime is 18809723. The next prime is 18809761. The reversal of 18809728 is 82790881.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18809723) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4773 + ... + 7771.

Almost surely, 2^18809728 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 18809728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21802500).

18809728 is an abundant number, since it is smaller than the sum of its proper divisors (24795272).

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

18809728 is an equidigital number, since it uses as much as digits as its factorization.

18809728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3027 (or 3008 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 43.

The square root of 18809728 is about 4337.0183306046. The cubic root of 18809728 is about 265.9464342739.

The spelling of 18809728 in words is "eighteen million, eight hundred nine thousand, seven hundred twenty-eight".