On Hee Haw what was the significance of Junior Samples' phone number, BR549?

On Hee Haw every week, they would have a short clip with Junior Samples as a used car salesman doing a television commercial. He would tell the viewers to call him at BR549. This brought on a lot of canned laughter. Was there any previous significance to this phone number? Was it funny because it was only a 5-digit phone number?