8080 = 6 means 6 circles 2022 = 1 means 1 circle 1999 = 3 means 3 circle

so 6666 = 4 means 4 circles

Consider the following pattern:

8809 = 6 7111 = 0 6666 = 4 7652 = 1 3368 = 3 9313 = 1 1008 = 4 9887 = 5 1155 = 0

What is 2021 = ?

If 9999=4 8888=8 1999=3 2222=0 Then 1616=?