Without delay, let's solve this. We've got 138 and we will be multiplying it by 207, that is, adding 138 to itself 207 times.
Step 1: 0 + 138 = 138
Step 2: 138 + 138 = 276
Step 3: 276 + 138 = 414
Step 4: 414 + 138 = 552
Step 5: 552 + 138 = 690
Step 6: 690 + 138 = 828
Step 7: 828 + 138 = 966
Step 8: 966 + 138 = 1104
Step 9: 1104 + 138 = 1242
Step 10: 1242 + 138 = 1380
Step 11: 1380 + 138 = 1518
Step 12: 1518 + 138 = 1656
Step 13: 1656 + 138 = 1794
Step 14: 1794 + 138 = 1932
Step 15: 1932 + 138 = 2070
Step 16: 2070 + 138 = 2208
Step 17: 2208 + 138 = 2346
Step 18: 2346 + 138 = 2484
Step 19: 2484 + 138 = 2622
Step 20: 2622 + 138 = 2760
Step 21: 2760 + 138 = 2898
Step 22: 2898 + 138 = 3036
Step 23: 3036 + 138 = 3174
Step 24: 3174 + 138 = 3312
Step 25: 3312 + 138 = 3450
Step 26: 3450 + 138 = 3588
Step 27: 3588 + 138 = 3726
Step 28: 3726 + 138 = 3864
Step 29: 3864 + 138 = 4002
Step 30: 4002 + 138 = 4140
Step 31: 4140 + 138 = 4278
Step 32: 4278 + 138 = 4416
Step 33: 4416 + 138 = 4554
Step 34: 4554 + 138 = 4692
Step 35: 4692 + 138 = 4830
Step 36: 4830 + 138 = 4968
Step 37: 4968 + 138 = 5106
Step 38: 5106 + 138 = 5244
Step 39: 5244 + 138 = 5382
Step 40: 5382 + 138 = 5520
Step 41: 5520 + 138 = 5658
Step 42: 5658 + 138 = 5796
Step 43: 5796 + 138 = 5934
Step 44: 5934 + 138 = 6072
Step 45: 6072 + 138 = 6210
Step 46: 6210 + 138 = 6348
Step 47: 6348 + 138 = 6486
Step 48: 6486 + 138 = 6624
Step 49: 6624 + 138 = 6762
Step 50: 6762 + 138 = 6900
Step 51: 6900 + 138 = 7038
Step 52: 7038 + 138 = 7176
Step 53: 7176 + 138 = 7314
Step 54: 7314 + 138 = 7452
Step 55: 7452 + 138 = 7590
Step 56: 7590 + 138 = 7728
Step 57: 7728 + 138 = 7866
Step 58: 7866 + 138 = 8004
Step 59: 8004 + 138 = 8142
Step 60: 8142 + 138 = 8280
Step 61: 8280 + 138 = 8418
Step 62: 8418 + 138 = 8556
Step 63: 8556 + 138 = 8694
Step 64: 8694 + 138 = 8832
Step 65: 8832 + 138 = 8970
Step 66: 8970 + 138 = 9108
Step 67: 9108 + 138 = 9246
Step 68: 9246 + 138 = 9384
Step 69: 9384 + 138 = 9522
Step 70: 9522 + 138 = 9660
Step 71: 9660 + 138 = 9798
Step 72: 9798 + 138 = 9936
Step 73: 9936 + 138 = 10074
Step 74: 10074 + 138 = 10212
Step 75: 10212 + 138 = 10350
Step 76: 10350 + 138 = 10488
Step 77: 10488 + 138 = 10626
Step 78: 10626 + 138 = 10764
Step 79: 10764 + 138 = 10902
Step 80: 10902 + 138 = 11040
Step 81: 11040 + 138 = 11178
Step 82: 11178 + 138 = 11316
Step 83: 11316 + 138 = 11454
Step 84: 11454 + 138 = 11592
Step 85: 11592 + 138 = 11730
Step 86: 11730 + 138 = 11868
Step 87: 11868 + 138 = 12006
Step 88: 12006 + 138 = 12144
Step 89: 12144 + 138 = 12282
Step 90: 12282 + 138 = 12420
Step 91: 12420 + 138 = 12558
Step 92: 12558 + 138 = 12696
Step 93: 12696 + 138 = 12834
Step 94: 12834 + 138 = 12972
Step 95: 12972 + 138 = 13110
Step 96: 13110 + 138 = 13248
Step 97: 13248 + 138 = 13386
Step 98: 13386 + 138 = 13524
Step 99: 13524 + 138 = 13662
Step 100: 13662 + 138 = 13800
Step 101: 13800 + 138 = 13938
Step 102: 13938 + 138 = 14076
Step 103: 14076 + 138 = 14214
Step 104: 14214 + 138 = 14352
Step 105: 14352 + 138 = 14490
Step 106: 14490 + 138 = 14628
Step 107: 14628 + 138 = 14766
Step 108: 14766 + 138 = 14904
Step 109: 14904 + 138 = 15042
Step 110: 15042 + 138 = 15180
Step 111: 15180 + 138 = 15318
Step 112: 15318 + 138 = 15456
Step 113: 15456 + 138 = 15594
Step 114: 15594 + 138 = 15732
Step 115: 15732 + 138 = 15870
Step 116: 15870 + 138 = 16008
Step 117: 16008 + 138 = 16146
Step 118: 16146 + 138 = 16284
Step 119: 16284 + 138 = 16422
Step 120: 16422 + 138 = 16560
Step 121: 16560 + 138 = 16698
Step 122: 16698 + 138 = 16836
Step 123: 16836 + 138 = 16974
Step 124: 16974 + 138 = 17112
Step 125: 17112 + 138 = 17250
Step 126: 17250 + 138 = 17388
Step 127: 17388 + 138 = 17526
Step 128: 17526 + 138 = 17664
Step 129: 17664 + 138 = 17802
Step 130: 17802 + 138 = 17940
Step 131: 17940 + 138 = 18078
Step 132: 18078 + 138 = 18216
Step 133: 18216 + 138 = 18354
Step 134: 18354 + 138 = 18492
Step 135: 18492 + 138 = 18630
Step 136: 18630 + 138 = 18768
Step 137: 18768 + 138 = 18906
Step 138: 18906 + 138 = 19044
Step 139: 19044 + 138 = 19182
Step 140: 19182 + 138 = 19320
Step 141: 19320 + 138 = 19458
Step 142: 19458 + 138 = 19596
Step 143: 19596 + 138 = 19734
Step 144: 19734 + 138 = 19872
Step 145: 19872 + 138 = 20010
Step 146: 20010 + 138 = 20148
Step 147: 20148 + 138 = 20286
Step 148: 20286 + 138 = 20424
Step 149: 20424 + 138 = 20562
Step 150: 20562 + 138 = 20700
Step 151: 20700 + 138 = 20838
Step 152: 20838 + 138 = 20976
Step 153: 20976 + 138 = 21114
Step 154: 21114 + 138 = 21252
Step 155: 21252 + 138 = 21390
Step 156: 21390 + 138 = 21528
Step 157: 21528 + 138 = 21666
Step 158: 21666 + 138 = 21804
Step 159: 21804 + 138 = 21942
Step 160: 21942 + 138 = 22080
Step 161: 22080 + 138 = 22218
Step 162: 22218 + 138 = 22356
Step 163: 22356 + 138 = 22494
Step 164: 22494 + 138 = 22632
Step 165: 22632 + 138 = 22770
Step 166: 22770 + 138 = 22908
Step 167: 22908 + 138 = 23046
Step 168: 23046 + 138 = 23184
Step 169: 23184 + 138 = 23322
Step 170: 23322 + 138 = 23460
Step 171: 23460 + 138 = 23598
Step 172: 23598 + 138 = 23736
Step 173: 23736 + 138 = 23874
Step 174: 23874 + 138 = 24012
Step 175: 24012 + 138 = 24150
Step 176: 24150 + 138 = 24288
Step 177: 24288 + 138 = 24426
Step 178: 24426 + 138 = 24564
Step 179: 24564 + 138 = 24702
Step 180: 24702 + 138 = 24840
Step 181: 24840 + 138 = 24978
Step 182: 24978 + 138 = 25116
Step 183: 25116 + 138 = 25254
Step 184: 25254 + 138 = 25392
Step 185: 25392 + 138 = 25530
Step 186: 25530 + 138 = 25668
Step 187: 25668 + 138 = 25806
Step 188: 25806 + 138 = 25944
Step 189: 25944 + 138 = 26082
Step 190: 26082 + 138 = 26220
Step 191: 26220 + 138 = 26358
Step 192: 26358 + 138 = 26496
Step 193: 26496 + 138 = 26634
Step 194: 26634 + 138 = 26772
Step 195: 26772 + 138 = 26910
Step 196: 26910 + 138 = 27048
Step 197: 27048 + 138 = 27186
Step 198: 27186 + 138 = 27324
Step 199: 27324 + 138 = 27462
Step 200: 27462 + 138 = 27600
Step 201: 27600 + 138 = 27738
Step 202: 27738 + 138 = 27876
Step 203: 27876 + 138 = 28014
Step 204: 28014 + 138 = 28152
Step 205: 28152 + 138 = 28290
Step 206: 28290 + 138 = 28428
Step 207: 28428 + 138 = 28566

So, 138*207 = 28566