GCD function
Returns the greatest common divisor of two or more integers. The greatest common divisor is the largest integer that divides both number1 and number2 without a remainder.
Syntax
GCD(number1,number2, ...)
Number1, number2, ... are 1 to 255 values. If any value is not an integer, it is truncated.
Remarks

If any argument is nonnumeric, GCD returns the #VALUE! error value.

If any argument is less than zero, GCD returns the #NUM! error value.

One divides any value evenly.

A prime number has only itself and one as even divisors.
Example
The example may be easier to understand if you copy it to a blank worksheet.
How to copy an example

Create a blank workbook or worksheet.

Select the example in the Help topic.
Note Do not select the row or column headers.
Selecting an example from Help

Press CTRL+C.

In the worksheet, select cell A1, and press CTRL+V.

To switch between viewing the results and viewing the formulas that return the results, press CTRL+` (grave accent), or on the Formulas tab, in the Formula Auditing group, click the Show Formulas button.

