It is another prefix recently adopted by the International System, along with Quetta and Ronna for multiples and quecto and ronto for submultiples. They are represented as follows: Queta as Q, Ronna as R, Quecto as q and ronto as r. In this case ronto- means or indicates a factor of 10-27 (one thousandth, on the Long Scale) and is used for submultiples or infinitely small parts. It is an the preceding 1 of 27 zeros. Ronto (symbol r) is a prefix adopted by Sistema Internacional in 2022. It is clarified that in the Short Scale used by Spanish-speaking countries the Ronto would be called 1 octillionth (because our system uses 3 zeros less).
It is a prefix for a value raised to the twenty-seventh negative power, such as 10 8315;² 8311; . It is taken from Greek 949; 957; 957; 949; 945; ( ennéa "nine" ) , and this needs two explanations: first, the 9 is because it counts groups of thousandths, of three zeros for decimals, and hence '27' because three zeros for decimal (0, 000) by nine gives 1/1000 8315; 8313; , or what is the same 0 , 000 82''000 82''000 82''000 82''000 82''000 82''000 82''000 82''001; and the name has added an r that is used as its symbol, because the e already has many other uses that could generate confusion, in addition to a /t/ which is a convention for submultiples that differentiates the pronunciation of the Ronna- multiple.
