18785728 has 56 divisors (see below), whose sum is σ = 40865552. Its totient is φ = 8515584.

The previous prime is 18785719. The next prime is 18785729. The reversal of 18785728 is 82758781.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18785729) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 55576 + ... + 55912.

It is an arithmetic number, because the mean of its divisors is an integer number (729742).

Almost surely, 2^18785728 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 18785728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20432776).

18785728 is an abundant number, since it is smaller than the sum of its proper divisors (22079824).

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

18785728 is a wasteful number, since it uses less digits than its factorization.

18785728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 429 (or 419 counting only the distinct ones).

The product of its digits is 250880, while the sum is 46.

The square root of 18785728 is about 4334.2505695910. The cubic root of 18785728 is about 265.8332759658.

The spelling of 18785728 in words is "eighteen million, seven hundred eighty-five thousand, seven hundred twenty-eight".