No problem, we've got 86147147 and 64753378 to multiply
86147147 × 64753378 = 64753378 × (86147147)
+ 64753378 × 7 what gives us 453273646
+ 64753378 × 40 that results in 2590135120
+ 64753378 × 100 that equals 6475337800
+ 64753378 × 7000 giving us 453273646000
+ 64753378 × 40000 that equals 2590135120000
+ 64753378 × 100000 which equals 6475337800000
+ 64753378 × 6000000 that results in 388520268000000
+ 64753378 × 80000000 that is equal 5180270240000000

= 5578318773312566
