18985824 has 144 divisors (see below), whose sum is σ = 63567504. Its totient is φ = 5299200.

The previous prime is 18985793. The next prime is 18985831. The reversal of 18985824 is 42858981.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (144).

It is a self number, because there is not a number n which added to its sum of digits gives 18985824.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 40954 + ... + 41414.

It is an arithmetic number, because the mean of its divisors is an integer number (441441).

Almost surely, 2^18985824 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 18985824, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31783752).

18985824 is an abundant number, since it is smaller than the sum of its proper divisors (44581680).

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

18985824 is a wasteful number, since it uses less digits than its factorization.

18985824 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 501 (or 490 counting only the distinct ones).

The product of its digits is 184320, while the sum is 45.

The square root of 18985824 is about 4357.2725413956. The cubic root of 18985824 is about 266.7737847435.

The spelling of 18985824 in words is "eighteen million, nine hundred eighty-five thousand, eight hundred twenty-four".