It means that the number "i" is multiplied by itself, appearing six times as a factor:
i x i x i x i x i x i
Assuming that "i" is meant to represent the imaginary unit, that's the same as minus 1.
1,000,000. Or 10 to the 6th power. Not exactly sure about what you mean.
Ten to the 6th power is 1,000,000
13 to the 6th power equals 4,826,809
7 to the 6th power divided by 7 to the -3rd power = 40,359,862.8
Four to the 6th power is written as 46
-0.00000849985
7000000 - 5300000 = 1700000
4 to the 2nd power, to the 6th power is the same thing as 4 to the 64th power, which is 6.33 x 1049. (6.33 is estimated to the hundredth power)
2.3 times 10 to the 6th power = 2,300,000
7000000 - 5300000 = 1700000
17 to the power of 6 is 24,137,569
16 to the 6th = 16 777 216