Without delay, let's solve this. We've got 864 and we will be multiplying it by 6, that is, adding 864 to itself 6 times.
Step 1: 0 + 864 = 864
Step 2: 864 + 864 = 1728
Step 3: 1728 + 864 = 2592
Step 4: 2592 + 864 = 3456
Step 5: 3456 + 864 = 4320
Step 6: 4320 + 864 = 5184

So, 864*6 = 5184