Mike is planning to retire in $32$ years. He is thinking about opening a retirement account and plans to invest an equal amount each year into the account. He expects to earn $10\mathrm{.}5\%$ per year in the account and is planning to have $$1,500,000$ in the account at retirement, what is the amount of Mike's annual investment?

$$7,922$

$$6,728$

$$5,387$

$$4,727$