Explanation: To write a number in scientific notation, first write a decimal point in the number so that there is only digit to the left of the decimal point.
So here, we can write 586400000 as 5.86400000 and notice that there is only one digit to the left of the decimal point.
Next, we count the number of places the decimal point would need to move to get back the original number which is 586400000.
Since we would need to move the decimal point 8 places to the right, we have an exponent of positive 5.
So we have 5.864 ×
In scientific notation, we will always have 10 before the exponent.
Finally, we can drop zeroes at the end of a decimal like I did above.