No problem, we've got 78372421 and 20991683 to multiply
78372421 × 20991683 = 20991683 × (78372421)
+ 20991683 × 1 that results in 20991683
+ 20991683 × 20 yielding 419833660
+ 20991683 × 400 producing 8396673200
+ 20991683 × 2000 resulting in 41983366000
+ 20991683 × 70000 giving us 1469417810000
+ 20991683 × 300000 yielding 6297504900000
+ 20991683 × 8000000 resulting in 167933464000000
+ 20991683 × 70000000 yielding 1469417810000000

= 1645169017574543
