There are many endowment plans and single premium plan marketed by insurance companies. One of them works this way.

You pay $1M upfront and 5 years later (60 months) later, you will receive income for life. The income is about 42k a year. After 5 years, your principal is guaranteed. Apparently, it is selling like hot cakes as people like guarantee products.

To me it is plain silly because there are like a billion alternative investment equally safe and more liquid.

For example, you can buy a portfolio of Unit Trust. First State dividend advantage, Schroder Asian Income, First State bridge, Schroder Asian Income etc. They are not the best but surely can generate 5% pa or more and pays you dividend straight away upon investing.

You can buy 4 different bonds of different tenure. For example SPH 3.2 2030, Wingtai 3.68 2030.
If you still think it is risky, then buy