Once you take your RMD, the money belongs to you, and what you do with it is entirely up to you. You can spend it, save it in a regular savings account, or invest it in a taxable brokerage account if you do not need it right away. What you cannot do is put the RMD back into a traditional IRA or roll it over into another tax-deferred retirement account, since that would defeat the purpose of the required distribution. You can, however, put the money into a Roth IRA if you have earned income that year and meet the income requirements for Roth contributions. For people who do not need the income, investing the RMD in a taxable account allows the money to keep working even after it has left the tax-sheltered environment.