7. For an integer, perform the following operation: write the sum of the last two digits at the end of the number. For example, starting from 2020, performing the operation 6 times results in 20202, 202022, 2020224, 20202246, 2020224610, 20202246101. Using this method, starting from 2020, after performing 2020 operations, the last two digits of the resulting number are $\qquad$
$13$