Apple Numbers '08 - Manual (Page 241)

Chapter 12 Dictionary of Functions 241
ISERROR
The ISERROR function returns TRUE if the expression in the function’s argument
evaluates to an error and FALSE otherwise.
ISERROR(cell)
 cell: A reference to a table cell that contains a formula.
ISEVEN
The ISEVEN function returns TRUE if the value is even (leaves no remainder when
divided by 2) and FALSE otherwise.
ISEVEN(number)
 number: A number, numeric expression, or reference to a cell containing a numeric
expression.
Notes
Fractional parts of a number are ignored.
Dates are not considered even or odd; if value is a date, an error is returned.
ISODD
The ISODD function returns TRUE if the value is odd (leaves a remainder when divided
by 2) and FALSE otherwise.
ISODD(number)
 number: A number, numeric expression, or reference to a cell containing a numeric
expression.
Notes
Fractional parts of a number are ignored.
Dates are not considered even or odd; if value is a date, an error is returned.
Examples
If cell A1 contains =QUOTIENT(3,0):
ISERROR(A1) returns TRUE. (You can’t divide by 0.)
Examples
ISEVEN(2) returns TRUE.
ISEVEN(2.75) returns TRUE.
ISEVEN(3) returns FALSE.