Square, cube, 4th power, 5th power,...n-th power.
In physics and math, the short form for base 10 is "to the Nth."
Examples:. 86 is "eight to the 6th power." 1021 is 10 to the 21st power, or, in short form "ten to the 21st."
BTW: For roots:根, it is square root, cube root, 4th root, 5th root... , and nth-root.