The amount of money you should roll over into an annuity depends ‌on your specific needs and goals. You want the amount to be enough to generate a lifetime income sufficient to cover your daily expenses. You should also factor in inflation and how much of your expenses are covered by other retirement income sources you receive, such as Social Security or pension payments.
A financial advisor can help determine which type of annuity is best suited for you and whether you should purchase any specific riders to modify the contract to meet your needs.