18934784 has 66 divisors (see below), whose sum is σ = 42323772. Its totient is φ = 8396800.

The previous prime is 18934781. The next prime is 18934793. The reversal of 18934784 is 48743981.

It is a Harshad number since it is a multiple of its sum of digits (44).

Its product of digits (193536) is a multiple of the sum of its prime divisors (54).

It is not an unprimeable number, because it can be changed into a prime (18934781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 461804 + ... + 461844.

Almost surely, 2^18934784 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 18934784, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21161886).

18934784 is an abundant number, since it is smaller than the sum of its proper divisors (23388988).

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

18934784 is an equidigital number, since it uses as much as digits as its factorization.

18934784 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 113 (or 54 counting only the distinct ones).

The product of its digits is 193536, while the sum is 44.

The square root of 18934784 is about 4351.4117249463. The cubic root of 18934784 is about 266.5345122957.

Multiplying 18934784 by its sum of digits (44), we get a square (833130496 = 28864²).

18934784 divided by its sum of digits (44) gives a square (430336 = 656²).

The spelling of 18934784 in words is "eighteen million, nine hundred thirty-four thousand, seven hundred eighty-four".