18224240 has 40 divisors (see below), whose sum is σ = 42787440. Its totient is φ = 7218176.

The previous prime is 18224191. The next prime is 18224243. The reversal of 18224240 is 4242281.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18224243) 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, 7496 + ... + 9624.

It is an arithmetic number, because the mean of its divisors is an integer number (1069686).

Almost surely, 2^18224240 is an apocalyptic number.

18224240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18224240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21393720).

18224240 is an abundant number, since it is smaller than the sum of its proper divisors (24563200).

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

18224240 is a wasteful number, since it uses less digits than its factorization.

18224240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2249 (or 2243 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 23.

The square root of 18224240 is about 4268.9858280393. The cubic root of 18224240 is about 263.1579383579.

The spelling of 18224240 in words is "eighteen million, two hundred twenty-four thousand, two hundred forty".