I think GUI is easiest so:
For the first one, set a variable to the amount of numbers you got (the numbers should be in an array)
Set HighestNumber (Real Variable) = Numbers[1]
Loop - 1-AmountVar
If Numbers[IntegerA] is greater than HighestNumber then
set HighestNumber = Numbers[IntegerA]
And the second: Set both into a real variable (if you havent already), then do:
Set X (real) = (Number1/number2)
If X = (convert real (X) into integer) then
set CanBeDivided = true (or something)
Else do
set CanBeDivided = false (or something)
(Havent got Editor on this comp, so I cant test this right now)