Square Root of 267

The square root of 267 is about 16.3401346384. It is irrational and already in simplest form, written √267.

Whole numbers, decimals or fractions like 9/16. Negative numbers have no real root.
Simplest radical form
√267
Decimal
16.3401346384
Both real square roots
±16.3401346384x² = 267 has two real solutions
Between
16² = 256 and 17² = 289so the root is between 16 and 17
Perfect power?
No
√26716.3401346384= √267

Show the work

  1. Prime-factor the radicand: 267 = 3 × 89.
  2. No prime appears 2 or more times, so √267 is already in simplest form.
  3. Decimal value: √267 ≈ 16.3401346384.
  4. Check: 16.34013463842 ≈ 267.

√267 at a glance

Exact value
√267
Decimal (10 places)
16.3401346384
Rounded
16.3 · 16.34 · 16.340
Perfect square?
No — between 16² and 17²
Rational?
Irrational
Both square roots
±16.340135
Prime factorization
3 × 89
Cube root
6.439277

How to simplify √267

The prime factorization of 267 is 3 × 89. Every prime appears only once, so there is no pair to bring outside the radical — √267 is already in simplest form (a "square-free" radicand).

A whole number has a rational square root only when every prime in its factorization appears an even number of times. In 267, 3 and 89 appear an odd number of times, so √267 is irrational and 16.3401346384 is a rounded value.

Where √267 sits between perfect squares

256 = 16² and 289 = 17² are the nearest perfect squares, so √267 lies between 16 and 17. 267 is 11 above 256 and 22 below 289, so the root is closer to 16.

√267 ≈ 16 + (267 − 256) ÷ (289 − 256) = 16 + 11/33 ≈ 16.3333
  • Straight line between 256 and 289: 16.3333 (0.04% low)
  • Tangent from 16, i.e. 16 + 11 ÷ 32: 16.3438 (0.02% high)
  • Tangent from 17, i.e. 17 − 22 ÷ 34: 16.3529 (0.08% high)

For √267 the tangent at 16 wins, missing by only 0.0036. Tangent estimates shine when the number sits close to a perfect square — here 267 is just 11 above 256.

1616² = 2561717² = 289√267 ≈ 16.3401
√267 on a number line, with tenths marked between 16 and 17.

Finding √267 with the Babylonian method

If a guess is too big, 267 ÷ x is too small by about the same amount, so their average lands much closer. In fact an error of e shrinks to roughly e² ÷ (2√267) in one step.

xnext = (x + 267 ÷ x) ÷ 2

Start from the nearest whole number, 16 (16² = 256):

StepGuess x267 ÷ xAverageCorrect decimals
116.000000000016.687500000016.34375000002
216.343750000016.336520076516.34013503826
316.340135038216.340134238516.3401346384all 10 shown

The count of correct decimals went 2, 6 and all 10 over 3 steps — roughly doubling each time — until the guess matched √267 = 16.3401346384 to every decimal shown.

√267 as a continued fraction

Every irrational square root has a continued fraction that repeats. For √267 the pattern is [16; 2, 1, 15, 1, 2, 32] with the block of 6 terms after the semicolon repeating forever. A pattern that never ends is one more proof that √267 is irrational.

Cutting the continued fraction off early gives the best fractions for approximating the root — no fraction with a smaller denominator comes closer:

FractionDecimalError
16/116.00000000003.4 × 10⁻¹
33/216.50000000001.6 × 10⁻¹
49/316.33333333336.8 × 10⁻³
768/4716.34042553192.9 × 10⁻⁴
817/5016.34000000001.3 × 10⁻⁴
2,402/14716.34013605441.4 × 10⁻⁶

The same fractions solve Pell’s equation, x² − 267y² = 1. Its smallest solution in positive whole numbers is x = 2,402, y = 147.

√267 in geometry and everyday measurements

  • A square patio or deck of 267 square feet is about 16.34 ft (16 ft 4 in) on each side, so edging all the way around takes 4 × √267 ≈ 65.4 ft.
  • 267 is not a sum of two whole-number squares — the prime factor 3 (one less than a multiple of 4) appears an odd number of times, which rules that out — so √267 is never the diagonal of a rectangle with whole-number sides. It is, however, the space diagonal of a 5 × 11 × 11 box, because 5² + 11² + 11² = 267.
RootSimplest formDecimalPerfect square?
√2642√6616.2481No
√265√26516.2788No
√266√26616.3095No
√267√26716.3401No
√2682√6716.3707No
√269√26916.4012No
√2703√3016.4317No
  • The cube root of 267 is about 6.439277.
  • Squaring undoes the root: (√267)² = 267, while 267² = 71,289 — the number whose square root is 267.

Frequently asked questions

What is the square root of 267?

The square root of 267 is √267, about 16.3401346384. The negative root, −16.340135, also squares to 267.

Is the square root of 267 rational or irrational?

Irrational. 267 is not a perfect square — it falls between 256 and 289 — and the square root of any whole number that is not a perfect square cannot be written as a fraction.

Can √267 be simplified?

No. 267 = 3 × 89 has no repeated prime factor, so there is no perfect square to take out of the radical.

What is √267 rounded to two decimal places?

√267 ≈ 16.34 to two decimal places (16.3 to one, 16.340 to three). Check: 16.34² = 266.9956, close to 267.

Need a different value? Use the Square root calculator, or browse the Square roots 1–1,000.