Square Root Calculator › Square root of 135

Square Root of 135

√135 ≈ 11.61895

135 is not a perfect square, so √135 is an irrational number that is approximately 11.61895. In simplified radical form, √135 = 3√15.

√135 lies between √121 = 11 and √144 = 12.

Number135
Square root (decimal)11.61895
Simplified radical3√15
Perfect square?No
Rational?No

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Prime factorization of 135

135 = 3^3 × 5. This is what determines the simplified radical: for √135 you pull out one copy of any prime that appears twice.

Here the paired factor 3 comes out from under the root, leaving √135 = 3√15.

Estimating √135 by hand

√135 falls between √121 = 11 and √144 = 12, so it starts at 11.something. The Babylonian method refines that guess by averaging it with 135 ÷ the guess:

StepEstimate
Start11
Step 111.636364
Step 211.618963
Step 311.61895

After 3 steps the estimate is 11.61895, matching √135 ≈ 11.61895.

Nearby square roots

√133 · √134 · √136 · √137

← Square root of 134 | Square root of 136 →

Frequently asked questions

Is 135 a perfect square?

No, 135 is not a perfect square, so its square root is irrational and approximately 11.61895.

What is the square root of 135 in simplest radical form?

√135 = 3√15 in simplest radical form.