Need help in Special Formatting Number

Here is one solution. You might consider adding more robust error handling.
if the decimal numbers passed to the div function are multiples i will be a non-zero number of that multiple otherwise i will be zero.

Dim i As Integer
i = div(12, 0)
If i = 0 Then
'not multiple
' do this
Else
' is multiple
' do something else
End If


Function div(ByVal numerator As Object, ByVal denominator As Object) As Integer
dim n , d decimal
Dim result As Decimal
Dim remainder As Decimal

If IsNumber(numerator) Is True _
And IsNumber(denominator) Is True Then
If numerator <> 0 Then
n = numerator
d = denominator
Else
GoTo error1
End If
Else
GoTo error1
End If
result = Decimal.divide(n, d)
remainder = Decimal.remainder(n, d)
If remainder = 0 Then
div = result
Else
div = 0
End If

Exit Function
error1:
msgbox("Numbers must be non-zero numerics", , "Multiple check error")
div = 0
End Function

End Function