Syntax GCD (x1, x2 *[,xi]*) Where xi=0..INTMAX
Location Math Package

The function GCD takes two or more positive integers and finds their greatest common denominator, ie. the largest number by which all of the given parameters can be divided without remainder. There is always such a number because 1 (the smallest common denominator) divides every number without remainder. GCD converts all passed values into integers by removing any decimal places (as with INT) before looking for the denominator.