Documentation/How Tos/Calc: ISNUMBER function
From Apache OpenOffice Wiki
Tests if a cell contains a number.
- Returns TRUE if value is a number or logical value and FALSE otherwise.
- ISNUMBER currently (OOo2.3) considers the logical values TRUE and FALSE as numbers. See Issues below.
- returns TRUE.
- returns FALSE.
- where D5 contains 99, returns TRUE, because D5 contains a number.
- ISNUMBER(A1) where A1 is a logical value, returns TRUE. This behaviour is not compatible with other competing spreadsheets. See issue 84266.