6540 g
Convert kilograms (kg) into grams (g) by multiplying the amount of kilograms (kg) by 1000 :
[tex]\boxed{\rm{6.45\:kg\:\:\:\:\:\:\:}}[/tex] times 1,000 --> [tex]\boxed{\rm{6540\:g\:\:\:\:}}[/tex]
[tex]\Large\text{6540\:g}[/tex]
[tex]\small\text{hope\:helpful~}[/tex]