Alright, let's solve this math problem step by step. First, we have the number 139. Next, we see the multiplication sign, which means we need to multiply something. And what are we multiplying it by? We multiply it by 13. So, we're going to take the number 139 and add it to itself 13 times.
Step 1: 0 + 139 = 139
Step 2: 139 + 139 = 278
Step 3: 278 + 139 = 417
Step 4: 417 + 139 = 556
Step 5: 556 + 139 = 695
Step 6: 695 + 139 = 834
Step 7: 834 + 139 = 973
Step 8: 973 + 139 = 1112
Step 9: 1112 + 139 = 1251
Step 10: 1251 + 139 = 1390
Step 11: 1390 + 139 = 1529
Step 12: 1529 + 139 = 1668
Step 13: 1668 + 139 = 1807

So, 139*13 = 1807