Square roots·√123
√123 =
√123
≈ 11.090537

Square root of 123 — 11.090537 (√123)

Irrational

The square root of 123 is about 11.090537, or exactly √123. It lies between 11 and 12.

As a decimal
≈ 11.090537
Simplified surd
√123 = √123
Between
11 < √123 < 12
Squared
123² = 15129
Cube root
∛123 ≈ 4.97319

Nearby numbers

√120 = 2√30√121 = 11√122 = √122√124 = 2√31√125 = 5√5√126 = 3√14

From 1 to 200

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How to read this

  • The decimal is rounded; the surd form is the exact value.
  • Pulling out a square factor simplifies the surd — √50 = 5√2.
  • If the number is not a perfect square, the decimal never ends (irrational).
  • Knowing which two integers it sits between is enough to estimate in your head.

Frequently asked questions

Q. What is the square root of 123?

About 11.090537, or exactly √123.

Q. Can the surd be simplified?

No — there is no square factor to pull out.

Q. Between which integers does it fall?

Between 11 and 12.

Q. What is the cube root of 123?

About 4.97319.