18020544 has 56 divisors (see below), whose sum is σ = 50493168. Its totient is φ = 5652480.

The previous prime is 18020537. The next prime is 18020549. The reversal of 18020544 is 44502081.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18020549) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 504 + ... + 6024.

Almost surely, 2^18020544 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 18020544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25246584).

18020544 is an abundant number, since it is smaller than the sum of its proper divisors (32472624).

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

18020544 is a wasteful number, since it uses less digits than its factorization.

18020544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5553 (or 5543 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 24.

The square root of 18020544 is about 4245.0611303019. The cubic root of 18020544 is about 262.1738061632.

The spelling of 18020544 in words is "eighteen million, twenty thousand, five hundred forty-four".