√138 ≈ 11.7473
√138 is an irrational number, so its decimals never end or repeat. It sits between 11 and 12 because 11² = 121 and 12² = 144.
| Decimal places | Value |
|---|---|
| 0 | 12 |
| 1 | 11.7 |
| 2 | 11.75 |
| 3 | 11.747 |
| 4 | 11.7473 |
| 5 | 11.74734 |
| 10 (digits) | 11.7473401245 |
138 has no perfect-square factor other than 1, so √138 is already in simplest radical form.
11.7473 × 11.7473 ≈ 137.9991, which is very close to 138.
Need another number? Use the square root calculator (also cube roots and other roots).
| Number | Square root |
|---|---|
| 134 | 11.5758 |
| 135 | 11.6190 |
| 136 | 11.6619 |
| 137 | 11.7047 |
| 139 | 11.7898 |
| 140 | 11.8322 |
| 141 | 11.8743 |
| 142 | 11.9164 |