Alright, let's work through 85656994 times 64306813 step by step
85656994 × 64306813 = 64306813 × (85656994)
+ 64306813 × 4 that is equal 257227252
+ 64306813 × 90 that equals 5787613170
+ 64306813 × 900 resulting in 57876131700
+ 64306813 × 6000 that results in 385840878000
+ 64306813 × 50000 that is equal 3215340650000
+ 64306813 × 600000 which equals 38584087800000
+ 64306813 × 5000000 producing 321534065000000
+ 64306813 × 80000000 giving us 5144545040000000

= 5508328295300122
