search.htm
UseNumericOperators {yes | no}
When set to "yes", the "<" and ">" signs are interpreted as numeric operators, or ignored otherwise. Default value is "no".
UseNumericOperators yes
the Section called Searching numbers in Chapter 8.
Affix, AlwaysFoundWord, Dehyphenate, IspellUsePrefixes, Spell, SQLWordForms, StopwordFile, Synonym.