Those numbers, both before the decimal point, and after it, are known as the frequency.
You must have the exact frequency for the ILS or beacon, very near just won’t do anything.
These frequencies can change over the years, so it is very important to have the very latest and current information before you use it in flight. All aviation charts will have a date of issue and a date when valid, they’re published in advance so a pilot always has access to the current chart with the correct frequencies and procedures.
Hope this helps.