The square root of 24 rounded up to the nearest integer is 5. This is the limit to test our divisions because any number greater than 5 times 5 is greater than 24. So, we stop at 5.
Let's test the values 1 through 5 for division into 24.

24/1 = 24. Remainder = 0. So, 24 and 1 are factors.

24/2 = 12. Remainder = 0. So, 12 and 2 are factors.

24/3 = 8. Remainder = 0. So, 8 and 3 are factors.

24/4 = 6. Remainder = 0. So, 6 and 4 are factors.

24/5 = 4. Remainder = 4. So, 4 isn't a factor.
Factors of a number 'x' are numbers that can divide 'x' without remainder, ie, remainder = 0. So, choosing only the numbers that meet this criteria from the list above, we find that the numbers which divide 24 (including 24) with no remainder are: 24, 12, 8, 6, 4, 3, 2, 1.
So, the factors of the number 24 are: 24, 12, 8, 6, 4, 3, 2, 1.
A composite number has more than two factors. A prime number has only two factors: 1 and itself. The number 1 is neither prime nor composite.
Because the number 24 has 8 factors, it is termed a composite number in mathematics.