how does math between a string and integer work?

[3Y3]

Say i put the following line of code in my director 8 message window

put "z"+1


it then gives me the answer

-- 1740089

but if i do the exact same code again it will keep giving me a new answer evry time.



-- 1773805

-- 1772845

-- 1740809


How exactly does this work out, how is it calculated?
Not really relevant to anything i'm working on, it just confuses me and I would like to know just in cas this ever comes up


3Y3