Casting / converting) from int to string (file under n00b)

Sorry for the heavily n00b’ed question (I’m sure I’ll have more to come).

I am trying to covert an int to string (generating a random hex number)
Along the way I did something like this for debugging.

    foofoofoo = "#" + str(5) + "0" + str(5) + "0" + str(5) + "0" 
    Print foofoofoo

Each time this is printed out with a space in front of each 5.
The printed string looks like:

# 50 50 50

Any ideas why these spaces are in there?
And more importantly how can I eliminate the spaces?

The space is where the sign would go if the number were negative. The ToStr() function, documented on p42 of the BrightScript Reference Manual will not add that space.