Without delay, let's solve this. We've got 819 and we will be multiplying it by 23, that is, adding 819 to itself 23 times.
Step 1: 0 + 819 = 819
Step 2: 819 + 819 = 1638
Step 3: 1638 + 819 = 2457
Step 4: 2457 + 819 = 3276
Step 5: 3276 + 819 = 4095
Step 6: 4095 + 819 = 4914
Step 7: 4914 + 819 = 5733
Step 8: 5733 + 819 = 6552
Step 9: 6552 + 819 = 7371
Step 10: 7371 + 819 = 8190
Step 11: 8190 + 819 = 9009
Step 12: 9009 + 819 = 9828
Step 13: 9828 + 819 = 10647
Step 14: 10647 + 819 = 11466
Step 15: 11466 + 819 = 12285
Step 16: 12285 + 819 = 13104
Step 17: 13104 + 819 = 13923
Step 18: 13923 + 819 = 14742
Step 19: 14742 + 819 = 15561
Step 20: 15561 + 819 = 16380
Step 21: 16380 + 819 = 17199
Step 22: 17199 + 819 = 18018
Step 23: 18018 + 819 = 18837

So, 819*23 = 18837