Alright, let's solve this math problem step by step. First, we have the number 620. Next, we see the multiplication sign, which means we need to multiply something. And what are we multiplying it by? We multiply it by 139. So, we're going to take the number 620 and add it to itself 139 times.
Step 1: 0 + 620 = 620
Step 2: 620 + 620 = 1240
Step 3: 1240 + 620 = 1860
Step 4: 1860 + 620 = 2480
Step 5: 2480 + 620 = 3100
Step 6: 3100 + 620 = 3720
Step 7: 3720 + 620 = 4340
Step 8: 4340 + 620 = 4960
Step 9: 4960 + 620 = 5580
Step 10: 5580 + 620 = 6200
Step 11: 6200 + 620 = 6820
Step 12: 6820 + 620 = 7440
Step 13: 7440 + 620 = 8060
Step 14: 8060 + 620 = 8680
Step 15: 8680 + 620 = 9300
Step 16: 9300 + 620 = 9920
Step 17: 9920 + 620 = 10540
Step 18: 10540 + 620 = 11160
Step 19: 11160 + 620 = 11780
Step 20: 11780 + 620 = 12400
Step 21: 12400 + 620 = 13020
Step 22: 13020 + 620 = 13640
Step 23: 13640 + 620 = 14260
Step 24: 14260 + 620 = 14880
Step 25: 14880 + 620 = 15500
Step 26: 15500 + 620 = 16120
Step 27: 16120 + 620 = 16740
Step 28: 16740 + 620 = 17360
Step 29: 17360 + 620 = 17980
Step 30: 17980 + 620 = 18600
Step 31: 18600 + 620 = 19220
Step 32: 19220 + 620 = 19840
Step 33: 19840 + 620 = 20460
Step 34: 20460 + 620 = 21080
Step 35: 21080 + 620 = 21700
Step 36: 21700 + 620 = 22320
Step 37: 22320 + 620 = 22940
Step 38: 22940 + 620 = 23560
Step 39: 23560 + 620 = 24180
Step 40: 24180 + 620 = 24800
Step 41: 24800 + 620 = 25420
Step 42: 25420 + 620 = 26040
Step 43: 26040 + 620 = 26660
Step 44: 26660 + 620 = 27280
Step 45: 27280 + 620 = 27900
Step 46: 27900 + 620 = 28520
Step 47: 28520 + 620 = 29140
Step 48: 29140 + 620 = 29760
Step 49: 29760 + 620 = 30380
Step 50: 30380 + 620 = 31000
Step 51: 31000 + 620 = 31620
Step 52: 31620 + 620 = 32240
Step 53: 32240 + 620 = 32860
Step 54: 32860 + 620 = 33480
Step 55: 33480 + 620 = 34100
Step 56: 34100 + 620 = 34720
Step 57: 34720 + 620 = 35340
Step 58: 35340 + 620 = 35960
Step 59: 35960 + 620 = 36580
Step 60: 36580 + 620 = 37200
Step 61: 37200 + 620 = 37820
Step 62: 37820 + 620 = 38440
Step 63: 38440 + 620 = 39060
Step 64: 39060 + 620 = 39680
Step 65: 39680 + 620 = 40300
Step 66: 40300 + 620 = 40920
Step 67: 40920 + 620 = 41540
Step 68: 41540 + 620 = 42160
Step 69: 42160 + 620 = 42780
Step 70: 42780 + 620 = 43400
Step 71: 43400 + 620 = 44020
Step 72: 44020 + 620 = 44640
Step 73: 44640 + 620 = 45260
Step 74: 45260 + 620 = 45880
Step 75: 45880 + 620 = 46500
Step 76: 46500 + 620 = 47120
Step 77: 47120 + 620 = 47740
Step 78: 47740 + 620 = 48360
Step 79: 48360 + 620 = 48980
Step 80: 48980 + 620 = 49600
Step 81: 49600 + 620 = 50220
Step 82: 50220 + 620 = 50840
Step 83: 50840 + 620 = 51460
Step 84: 51460 + 620 = 52080
Step 85: 52080 + 620 = 52700
Step 86: 52700 + 620 = 53320
Step 87: 53320 + 620 = 53940
Step 88: 53940 + 620 = 54560
Step 89: 54560 + 620 = 55180
Step 90: 55180 + 620 = 55800
Step 91: 55800 + 620 = 56420
Step 92: 56420 + 620 = 57040
Step 93: 57040 + 620 = 57660
Step 94: 57660 + 620 = 58280
Step 95: 58280 + 620 = 58900
Step 96: 58900 + 620 = 59520
Step 97: 59520 + 620 = 60140
Step 98: 60140 + 620 = 60760
Step 99: 60760 + 620 = 61380
Step 100: 61380 + 620 = 62000
Step 101: 62000 + 620 = 62620
Step 102: 62620 + 620 = 63240
Step 103: 63240 + 620 = 63860
Step 104: 63860 + 620 = 64480
Step 105: 64480 + 620 = 65100
Step 106: 65100 + 620 = 65720
Step 107: 65720 + 620 = 66340
Step 108: 66340 + 620 = 66960
Step 109: 66960 + 620 = 67580
Step 110: 67580 + 620 = 68200
Step 111: 68200 + 620 = 68820
Step 112: 68820 + 620 = 69440
Step 113: 69440 + 620 = 70060
Step 114: 70060 + 620 = 70680
Step 115: 70680 + 620 = 71300
Step 116: 71300 + 620 = 71920
Step 117: 71920 + 620 = 72540
Step 118: 72540 + 620 = 73160
Step 119: 73160 + 620 = 73780
Step 120: 73780 + 620 = 74400
Step 121: 74400 + 620 = 75020
Step 122: 75020 + 620 = 75640
Step 123: 75640 + 620 = 76260
Step 124: 76260 + 620 = 76880
Step 125: 76880 + 620 = 77500
Step 126: 77500 + 620 = 78120
Step 127: 78120 + 620 = 78740
Step 128: 78740 + 620 = 79360
Step 129: 79360 + 620 = 79980
Step 130: 79980 + 620 = 80600
Step 131: 80600 + 620 = 81220
Step 132: 81220 + 620 = 81840
Step 133: 81840 + 620 = 82460
Step 134: 82460 + 620 = 83080
Step 135: 83080 + 620 = 83700
Step 136: 83700 + 620 = 84320
Step 137: 84320 + 620 = 84940
Step 138: 84940 + 620 = 85560
Step 139: 85560 + 620 = 86180

So, 620*139 = 86180