Excel: FACT() and Functions Using Factorials Return #NUM!

ID: Q115796

2.x 3.00 4.00 4.00a 5.00 5.00c 7.00 7.00a | 2.x 3.00 | 2.20 3.00 4.00 5.00 5.00a

WINDOWS                  | OS/2     | MACINTOSH

The information in this article applies to:

Microsoft Excel for Windows 95, versions 7.0, 7.0a
Microsoft Excel for Windows, versions 2.x, 3.0, 4.0, 4.0a, 5.0, 5.0c
Microsoft Excel for OS/2, versions 2.x, 3.0
Microsoft Excel for the Macintosh, versions 2.2, 3.0, 4.0, 5.0, 5.0a

SUMMARY

In Microsoft Excel, you will receive a #NUM! error if you do either of the following:

- Use the FACT() function with an argument that exceeds 170

  -or-

- Use any function that computes the factorial of a number that exceeds

MORE INFORMATION

The factorial of a number is equal to the value of this sequence:

   factorial = 1 * 2 * 3 * 4 * .... * number

The number must be an integer greater than or equal to zero.

The error occurs because the maximum number that can be computed by Microsoft Excel is 9.9999E+307. The factorial of 170 is 7.2574E+306: this number can be properly computed by Microsoft Excel.

However, the factorial of 171 is greater than the maximum number that Microsoft Excel can compute; therefore, if you attempt to compute the factorial of 171, you will receive a #NUM! error value.

Also, any function that computes a factorial as part of its computations will likewise result in a #NUM! error if the number whose factorial is being taken exceeds 170.

Functions in Microsoft Excel that use a factorial include (but are not limited to) the following:

   Function        Argument(s) for which factorial is computed
   ---------------------------------------------------------------
   COMBIN()        number, number_chosen, number - number_chosen
   FACT()          number
   FACTDOUBLE()    number (limit is 300: 301 or more causes #NUM!)
   MULTINOMIAL()   a + b + c, a, b, c
   PERMUT()        number, number - number_chosen
   POISSON()       x

In the above functions,if the argument (or combination of arguments) shown exceeds 170, the function will return a #NUM! error. Any calculations or formulas that reference the function in question will also return a #NUM! error.

For example, this formula will return a #NUM! error

   =MULTINOMIAL(2,3,166)

because the factorial of the sum of a, b, and c (2 + 3 + 166 = 171) cannot be computed.

KBCategory: kbusage KBSubcategory:

Additional reference words: 3.00 3.00a 4.00 4.00a 5.00 5.00a 5.00c 7.00 7.00a

Version           : 2.x 3.00 4.00 4.00a 5.00 5.00c 7
Platform          : WINDOWS

Last Reviewed: March 29, 1997