Alright, let's solve this math problem step by step. First, we have the number 621. Next, we see the multiplication sign, which means we need to multiply something. And what are we multiplying it by? We multiply it by 125. So, we're going to take the number 621 and add it to itself 125 times.
Step 1: 0 + 621 = 621
Step 2: 621 + 621 = 1242
Step 3: 1242 + 621 = 1863
Step 4: 1863 + 621 = 2484
Step 5: 2484 + 621 = 3105
Step 6: 3105 + 621 = 3726
Step 7: 3726 + 621 = 4347
Step 8: 4347 + 621 = 4968
Step 9: 4968 + 621 = 5589
Step 10: 5589 + 621 = 6210
Step 11: 6210 + 621 = 6831
Step 12: 6831 + 621 = 7452
Step 13: 7452 + 621 = 8073
Step 14: 8073 + 621 = 8694
Step 15: 8694 + 621 = 9315
Step 16: 9315 + 621 = 9936
Step 17: 9936 + 621 = 10557
Step 18: 10557 + 621 = 11178
Step 19: 11178 + 621 = 11799
Step 20: 11799 + 621 = 12420
Step 21: 12420 + 621 = 13041
Step 22: 13041 + 621 = 13662
Step 23: 13662 + 621 = 14283
Step 24: 14283 + 621 = 14904
Step 25: 14904 + 621 = 15525
Step 26: 15525 + 621 = 16146
Step 27: 16146 + 621 = 16767
Step 28: 16767 + 621 = 17388
Step 29: 17388 + 621 = 18009
Step 30: 18009 + 621 = 18630
Step 31: 18630 + 621 = 19251
Step 32: 19251 + 621 = 19872
Step 33: 19872 + 621 = 20493
Step 34: 20493 + 621 = 21114
Step 35: 21114 + 621 = 21735
Step 36: 21735 + 621 = 22356
Step 37: 22356 + 621 = 22977
Step 38: 22977 + 621 = 23598
Step 39: 23598 + 621 = 24219
Step 40: 24219 + 621 = 24840
Step 41: 24840 + 621 = 25461
Step 42: 25461 + 621 = 26082
Step 43: 26082 + 621 = 26703
Step 44: 26703 + 621 = 27324
Step 45: 27324 + 621 = 27945
Step 46: 27945 + 621 = 28566
Step 47: 28566 + 621 = 29187
Step 48: 29187 + 621 = 29808
Step 49: 29808 + 621 = 30429
Step 50: 30429 + 621 = 31050
Step 51: 31050 + 621 = 31671
Step 52: 31671 + 621 = 32292
Step 53: 32292 + 621 = 32913
Step 54: 32913 + 621 = 33534
Step 55: 33534 + 621 = 34155
Step 56: 34155 + 621 = 34776
Step 57: 34776 + 621 = 35397
Step 58: 35397 + 621 = 36018
Step 59: 36018 + 621 = 36639
Step 60: 36639 + 621 = 37260
Step 61: 37260 + 621 = 37881
Step 62: 37881 + 621 = 38502
Step 63: 38502 + 621 = 39123
Step 64: 39123 + 621 = 39744
Step 65: 39744 + 621 = 40365
Step 66: 40365 + 621 = 40986
Step 67: 40986 + 621 = 41607
Step 68: 41607 + 621 = 42228
Step 69: 42228 + 621 = 42849
Step 70: 42849 + 621 = 43470
Step 71: 43470 + 621 = 44091
Step 72: 44091 + 621 = 44712
Step 73: 44712 + 621 = 45333
Step 74: 45333 + 621 = 45954
Step 75: 45954 + 621 = 46575
Step 76: 46575 + 621 = 47196
Step 77: 47196 + 621 = 47817
Step 78: 47817 + 621 = 48438
Step 79: 48438 + 621 = 49059
Step 80: 49059 + 621 = 49680
Step 81: 49680 + 621 = 50301
Step 82: 50301 + 621 = 50922
Step 83: 50922 + 621 = 51543
Step 84: 51543 + 621 = 52164
Step 85: 52164 + 621 = 52785
Step 86: 52785 + 621 = 53406
Step 87: 53406 + 621 = 54027
Step 88: 54027 + 621 = 54648
Step 89: 54648 + 621 = 55269
Step 90: 55269 + 621 = 55890
Step 91: 55890 + 621 = 56511
Step 92: 56511 + 621 = 57132
Step 93: 57132 + 621 = 57753
Step 94: 57753 + 621 = 58374
Step 95: 58374 + 621 = 58995
Step 96: 58995 + 621 = 59616
Step 97: 59616 + 621 = 60237
Step 98: 60237 + 621 = 60858
Step 99: 60858 + 621 = 61479
Step 100: 61479 + 621 = 62100
Step 101: 62100 + 621 = 62721
Step 102: 62721 + 621 = 63342
Step 103: 63342 + 621 = 63963
Step 104: 63963 + 621 = 64584
Step 105: 64584 + 621 = 65205
Step 106: 65205 + 621 = 65826
Step 107: 65826 + 621 = 66447
Step 108: 66447 + 621 = 67068
Step 109: 67068 + 621 = 67689
Step 110: 67689 + 621 = 68310
Step 111: 68310 + 621 = 68931
Step 112: 68931 + 621 = 69552
Step 113: 69552 + 621 = 70173
Step 114: 70173 + 621 = 70794
Step 115: 70794 + 621 = 71415
Step 116: 71415 + 621 = 72036
Step 117: 72036 + 621 = 72657
Step 118: 72657 + 621 = 73278
Step 119: 73278 + 621 = 73899
Step 120: 73899 + 621 = 74520
Step 121: 74520 + 621 = 75141
Step 122: 75141 + 621 = 75762
Step 123: 75762 + 621 = 76383
Step 124: 76383 + 621 = 77004
Step 125: 77004 + 621 = 77625

So, 621*125 = 77625