I got several calls from this same number. Like you, I ignored the first 4 times they called but eventually answered the phone. It's the corp office for Edward Jones Financial according to the lady I spoke with. They want me to switch my 401K to something with their company.
This number is for Edward Jones Investments home office in St Louis, if you live in St Louis and have an account with them or talked to a financial advisor it is probably them calling.