Factor

Define factor:

Let us start by defining "factor", the word on the extreme right of the term "highest common factor". From out of plenty of meanings of the word one specific meaning is used here. They say that number x is a factor of number y, if they can find another number k such that y = k x. Alternatively, they can also say that on dividing y by x (y as dividend and x as quotient) they get a remainder of zero.

Ex:1 (Factors of 4)
Factors of 4 are: 1, 2, 4
Ex:2 (Factors of 12)
Factors of 12 are: 1, 2, 3, 4, 6, 12
Notice that 1 and the number itself will always be among the factors of a number. It is natural, because for any number x, they have x = 1 * x and also x = x * 1.

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