This is a program rather than a sub. It is 160 chars without unnecessary whitespace. I don't know what you are supposed to do with 1 and 0. Get another phone number I guess. ;-)

#!/usr/bin/perl -snl

BEGIN{
    for ($N) {
        s/[10]//g;
        s/2/[abc]/g;
        s/3/[def]/g;
        s/4/[ghi]/g;
        s/5/[jkl]/g;
        s/6/[mno]/g;
        s/7/[pqrs]/g;
        s/8/[tuv]/g;
        s/9/[wxyz]/g
    }
}

/^$N$/oi&&print
[download]

You can run it like this:     phonenum -N=7375 /usr/dict/words
I tried this with most of my friends' and family's phone numbers and none of them generated any words. :-(

John.
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