If you want a pronounciation dictionary, then the
cmu dictionary might
be what you're looking for (125,000+ words plus phonetic transcriptions).
You may have to adjust the mapping of phonemes to digits (it has
separate phonemes for NG, for TH as in thee vs. TH as in theta). But
it is certainly something you can work with to develop your data file
of numbers to words --- I just did so in a few minutes.
Somewhat OT, but for those just looking for a large wordlist you might
check out the yawl list available
here, it
has 263,533 entries ...by comparison, the stock /usr/share/dict/words
file that came with my slackware distro has 38,619 entries.
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