Answer:
87,300,000,000,000,000
Explanation:
The E16 is a way to write ×10¹⁶ that is used by some computers, spreadsheets, and calculators. As with any decimal number, the exponent of 10 tells you the number of decimal places between the place with that value and the decimal point.
8.73E16 = 8.73×10¹⁶ = 87.3×10¹⁵ = 87.3 × 1,000,000,000,000,000
= 87,300,000,000,000,000
_____
Some places, the "standard form" is 8.73×10¹⁶.