No problem, we've got 81515544 and 48715097 to multiply
81515544 × 48715097 = 48715097 × (81515544)
+ 48715097 × 4 resulting in 194860388
+ 48715097 × 40 that results in 1948603880
+ 48715097 × 500 that equals 24357548500
+ 48715097 × 5000 that results in 243575485000
+ 48715097 × 10000 that equals 487150970000
+ 48715097 × 500000 what gives us 24357548500000
+ 48715097 × 1000000 what gives us 48715097000000
+ 48715097 × 80000000 that equals 3897207760000000

= 3971037632967768
