Alright, let's work through 64398425 times 9630975 step by step
64398425 × 9630975 = 9630975 × (64398425)
+ 9630975 × 5 that is equal 48154875
+ 9630975 × 20 which equals 192619500
+ 9630975 × 400 yielding 3852390000
+ 9630975 × 8000 what gives us 77047800000
+ 9630975 × 90000 producing 866787750000
+ 9630975 × 300000 giving us 2889292500000
+ 9630975 × 4000000 that equals 38523900000000
+ 9630975 × 60000000 resulting in 577858500000000

= 620219621214375
