$10.00 convert to Ten dollars
Try the Numbertext extension, it’s older and the compatibility list doesn’t explicitly mention, but it still works with LibreOffice 5.3. It adds two functions NUMBERTEXT and MONEYTEXT to Calc.
Since LibreOffice 6.1 there is a number format code [NatNum12] modifier. For example, [NatNum12 USD]0 will display ten U.S. dollars. See also online help.
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