eight-million five-hundred ninty-seven thousand = 8,597,000
It's very simple.. All you have to do it write out the number in words.
In scientific notation this is
$$8.597\times 10^{6}$$
You start with a non-zero digit, then put a decimal point, then the rest of the digits (apart from trailing zeros), then multiply by 10 to whatever power is necessary to match the original number.
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