Answer:
18000000
Explanation:
1.8x10^7 is the same as 18x10^6
which is the same as 180 x 10^5
which is the same as 1800 x 10^4
which is the same as 18000 x 10^3
which is the same as 180000 x 10^2
which is the same as 1800000 x 10
which is the same as 18000000 (six zeros)