We have: 1000 = \(2^3.5^3\)\(=20.2.5^2⋮20\)

=> 1000 : 2 \(⋮\) 20

1000 : 5 \(⋮\) 20

1000 : 2 x 5 \(⋮\) 20

1000 : \(\left(2.5^2\right)⋮\) 20

So there are 5 factors of 1000 can be divided by 20 without a remainder.

Lê Quốc Trần Anh selected this answer.