√66 = 8.1240384046. 66 is not a perfect square; the result is irrational.

Is 66 a perfect square?

No, 66 is not a perfect square. Its square root is irrational.

What is 8.1240384046 squared?

8.1240384046 squared is approximately 66. (8.1240384046)² ≈ 66

Instant answer with step-by-step solution

√66 = 8.1240384046

√66 = 8.1240384046

⚠ 66 is not a perfect square — result rounded to 10 significant figures

We need to find √66 — a number that when multiplied by itself equals 66.
66 is not a perfect square. Its square root is irrational.
It falls between √64 = 8 and √81 = 9.
Using the formula √N = N^(1/2): √66 = 66^0.5 = 8.1240384046
Verification: 8.1240384046 × 8.1240384046 ≈ 66 ✓ (rounded to 10 significant figures)

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