When searching for some issues based on the "Number Field" custom field type, there may be a requirement to search issues for a range of numbers based on the custom field.
The "Number Field" custom field type can be configured to use the "Number range searcher". Hence, the issues can be searched within a range of values for that customfield. The search template can be changed by clicking on the "Edit" operation via Administration -> Issue Fields -> Custom Fields. For more information, please refer to the custom field documentation
Please note that a re-index needs to be performed via Administration -> System -> Indexing after changing the custom field searcher.