Learn how to say Quintillion correctly in English with this tutorial pronunciation video.
Oxford dictionary definition of the word quintillion:
cardinal number (plural quintillions or (with numeral) same )
a thousand raised to the power of six (1018).
dated, chiefly British a million raised to the power of five (1030).
late 17th century: from French, from million, by substitution of the prefix quinti- ‘five’ (from Latin quintus ‘fifth’) for the initial letters