The reason that this is an important question is that I remember Craig Ball mentioning that in one of the requirements for good eDiscovery software. So OK, I ran a few searches and found out that out-of-the-box FreeEed does index all numbers. That felt good, and I am attaching the screenshots of the experiment.
Of course, that is not a special property of FreeEed but of Tika, Lucene, and SOLR. It's these components that are responsible for what FreeEed indexes.
Had this not been the case, I would tweak the use of the components, but luckily this was the way FreeEed already uses them. The advantage of passing through to these libraries is that the users can rely on the well-known Lucene syntax to do their searches.
