how do I factor a number down to one digit?

[Allan]

I'm trying to write a numerology program where I have each letter
identified by a numerical value like
a=1
b=2
c=3
as so forth. I then input a name. How do I treat each letter as a
single value? That is, instead of print myname I have to do a print
m+y+n+a+m+e which returns a number. I next want to convert the
resulting two or three digit number to a single digit. Like 123 would
be 1+2+3 returning a 5. I hope this isn't too stupid of a question.