Alright, let's work through 72688560 times 86666791 step by step
72688560 × 86666791 = 86666791 × (72688560)
+ 86666791 × 0 that is equal 0
+ 86666791 × 60 that results in 5200007460
+ 86666791 × 500 that is equal 43333395500
+ 86666791 × 8000 resulting in 693334328000
+ 86666791 × 80000 that is equal 6933343280000
+ 86666791 × 600000 that equals 52000074600000
+ 86666791 × 2000000 yielding 173333582000000
+ 86666791 × 70000000 giving us 6066675370000000

= 6299684237610960
