They call a couple times in the a.m. on weekdays.  They never leave a message on the machine, but occasionally someone says, 'hello?, hello?', and that's it.  Saw another website where someone posted that it is a cash advance service, but have not seen or heard anything to corroborate that statement.
Searches indicate that the number is located in Hawthorne, CA, but some sites say it is a land-line, while others indicate it is a wireless number.