ISNUMBER

Definition: ISNUMBER is a function that returns TRUE if a value is a number, and FALSE if it is not.

Syntax: =ISNUMBER(value)

Situation: This formula is appropriate when you need to check if a value is a number.

Example: If you want to check if cell A1 contains a number, the formula =ISNUMBER(A1) will return TRUE if it contains a number, and FALSE if it does not.