"1" messing up prime no. module

I don't know how to write modules yet, so I downloaded the one below. It checks to see if a number is a prime. It's cool and works, except any time that a 1 comes up. When I referrence a cell (B2 for example)that's value =1, with =isprime(B2), then I recieve "# value" as a result. This messes up the rest of my spreadsheet.

Function IsPrime(ByRef rngVal As Range) As Variant
Dim ValPrime As Boolean
Dim x As Long
Dim ValGCD As Double
Dim Val As Double

Val = rngVal.Value

If Val = 1 Or Val < 0 Or Val <> Int(Val) Or IsEmpty(rngVal) = True Then
IsPrime = "#VALUE"
Exit Function
End If

ValPrime = True

For x = 2 To Val - 1
If Val / x = Int(Val / x) Then
ValPrime = False
IsPrime = ValPrime
Exit Function
End If

Next x

IsPrime = ValPrime

End Function

Can someone pleace help me with this?