The square root of 400 is 20.
The square root of 400 is 20.
Because 20 × 20 = 400, 400 is a perfect square and its root is a whole number.
You can check it by squaring the result: 20² ≈ 400.
| √400 | = 20 |
| 20² | = 400 |
| ∛400 | = 7.368063 |
| Number | Square root | Note |
|---|---|---|
| 196 | 14 | perfect square |
| 225 | 15 | perfect square |
| 256 | 16 | perfect square |
| 289 | 17 | perfect square |
| 324 | 18 | perfect square |
| 361 | 19 | perfect square |
| 400 | 20 | this page |
| 500 | 22.36068 |
The square root of 400 is 20.
Yes. 20 × 20 = 400.
Rational, because it is the whole number 20.
The cube root of 400 is about 7.368063.
Yes. Use the calculator on this page, or open the full free Scientific Calculator with memory, history and keyboard support.