18865224 has 80 divisors (see below), whose sum is σ = 60403200. Its totient is φ = 5388768.

The previous prime is 18865213. The next prime is 18865229. The reversal of 18865224 is 42256881.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (18865229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 2457 + ... + 6615.

It is an arithmetic number, because the mean of its divisors is an integer number (755040).

Almost surely, 2^18865224 is an apocalyptic number.

18865224 is a gapful number since it is divisible by the number (14) 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 18865224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30201600).

18865224 is an abundant number, since it is smaller than the sum of its proper divisors (41537976).

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

18865224 is a wasteful number, since it uses less digits than its factorization.

18865224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4184 (or 4171 counting only the distinct ones).

The product of its digits is 30720, while the sum is 36.

The square root of 18865224 is about 4343.4115623551. The cubic root of 18865224 is about 266.2077258810.

The spelling of 18865224 in words is "eighteen million, eight hundred sixty-five thousand, two hundred twenty-four".