The answer to the problem she entered was 1,600,000,000,000.
But most calculator displays show 10 digits, so anything larger
than 999,999,999 could not display.
Instead, the calculator is designed to show very large (or very small) numbers
using scientific notation. In that format, her answer is displayed as
1.6 x 10¹² , or, on the calculator, 1.6 E+12. The 'E' means 'exponent of 10".