If the cell or calculation is a numeric value the result TRUE is shown.
If the cell or calculation is not numeric, or is blank, the result FALSE is shown.
The cell to test can be a cell reference or a calculation.
No special formatting is needed.
The following table was used by a personnel department to lookup the salary of an employee.
The =ISNUMBER() function has been used to identify the type of entry made, and then
the =IF() decides which VLOOKUP to perform.