How do I do Block math? (continued)

For function 1, it will run whenever the part is touched, and because of the way Lua works, multiple threads running the function can happen if multiple collisions are detected. To solve this, we have (what people like to call) debounce.

number1 = script.Parent.Name; --The name is 0
number2 = 1;
number3 = 10;
number4 = 40;
number5 = 250;

debounce = false --Here's debounce, which is initially false.

function onTouched()
    if debounce == true then return end --Don't run the function if debounce is true, otherwise
    debounce = true --Set debounce to true so the function can't run until we set it back to false.
    print(number1+number2) --Continue with the function.
    script.Parent.Name = (number1+number2)
    wait(0.2)
    print "ahh" 
    debounce = false --We did what we needed, so we set debounce back to false.
end

script.Parent.Touched:connect(onTouched)

Function 2 is not running simply because you never called it; it's just sitting there waiting to be called. You need to call the function, like so:

function math()
if script.Parent.Name == "50" then --Since names are strings, we enclose them in single or double quotation marks.
    script.Parent.TopSurface = "Studs"
end

math() --Actually call, or run, math

Full script:

number1 = script.Parent.Name
number2 = 1;
number3 = 10;
number4 = 40;
number5 = 250;

debounce = false

function math()
    if script.Parent.Name == "50" then
        script.Parent.TopSurface = "Studs"
    end
end

function onTouched()
    if debounce == true then return end
    debounce = true
    number1 = script.Parent.Name
    print(number1+number2) 
    script.Parent.Name = (number1+number2)
    wait(0.2)
    print "ahh"
    math()
    debounce = false
end

script.Parent.Touched:connect(onTouched)