I've run into a problem indexing/searching for a string that has too many digits in it. The number of digits seems to vary a bit, but it seems to fail at around 10 consecutive digits or more. Here are some examples of indexed fields and the search terms that are either failing or succeeding. I'm indexing this field as a keyword (Field.Index.UN_TOKENIZED, Field.Store.YES) and using a standard analyzer for everything.
indexed: 1212121212121212 failed search: 1212121212121212 121212121212121* 12121212121212* 1212121212121* 121212121212* 12121212121* successful search: 1212121212* 121212121* 12121212* 1212121* 121212* //The alpha characters breaking up the numbers seem make this string properly searchable. indexed: 1212f1212f1212f1 successful search: 1212f1212f1212f1 1212f1212f1212f* indexed: a121212121212121 failed search: a121212121212121 a12121212121212* a1212121212121* a121212121212* a12121212121* successful search: a1212121212* a121212121* a12121212* a1212121* indexed: a999999999999999 failed search: a999999999999999 successful search: a99999999999999* indexed: 9999999999999999 failed search: 9999999999999999 successful search: 999999999999999*