Square Root of 271

The square root of 271 is about 16.4620776332. It is irrational and already in simplest form, written √271.

Whole numbers, decimals or fractions like 9/16. Negative numbers have no real root.
Simplest radical form
√271
Decimal
16.4620776332
Both real square roots
±16.4620776332x² = 271 has two real solutions
Between
16² = 256 and 17² = 289so the root is between 16 and 17
Perfect power?
No
√27116.4620776332= √271

Show the work

  1. Prime-factor the radicand: 271 = 271.
  2. No prime appears 2 or more times, so √271 is already in simplest form.
  3. Decimal value: √271 ≈ 16.4620776332.
  4. Check: 16.46207763322 ≈ 271.

√271 at a glance

Exact value
√271
Decimal (10 places)
16.4620776332
Rounded
16.5 · 16.46 · 16.462
Perfect square?
No — between 16² and 17²
Rational?
Irrational
Both square roots
±16.462078
Prime factorization
271
Cube root
6.471274

How to simplify √271

271 is a prime number, so its only factors are 1 and 271. There is no perfect-square factor to pull out, which means √271 is already in its simplest radical form.

The square root of any prime is irrational. If √271 were a fraction a/b in lowest terms, then a² = 271b², so 271 would divide a — and then 271 would divide b too, contradicting “lowest terms.” That is why the decimal 16.4620776332 is only a rounded value.

Where √271 sits between perfect squares

256 = 16² and 289 = 17² are the nearest perfect squares, so √271 lies between 16 and 17. 271 is 15 above 256 and 18 below 289, so the root is closer to 16.

√271 ≈ 16 + (271 − 256) ÷ (289 − 256) = 16 + 15/33 ≈ 16.4545
  • Straight line between 256 and 289: 16.4545 (0.05% low)
  • Tangent from 16, i.e. 16 + 15 ÷ 32: 16.4688 (0.04% high)
  • Tangent from 17, i.e. 17 − 18 ÷ 34: 16.4706 (0.05% high)

For √271 the tangent at 16 wins, missing by only 0.0067. Tangent estimates shine when the number sits close to a perfect square — here 271 is just 15 above 256.

1616² = 2561717² = 289√271 ≈ 16.4621
√271 on a number line, with tenths marked between 16 and 17.

Finding √271 with the Babylonian method

If a guess is too big, 271 ÷ 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√271) in one step.

xnext = (x + 271 ÷ x) ÷ 2

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

StepGuess x271 ÷ xAverageCorrect decimals
116.000000000016.937500000016.46875000002
216.468750000016.455407969616.46207898485
316.462078984816.462076281516.4620776332all 10 shown

The count of correct decimals went 2, 5 and all 10 over 3 steps — roughly doubling each time — until the guess matched √271 = 16.4620776332 to every decimal shown.

√271 as a continued fraction

Every irrational square root has a continued fraction that repeats. For √271 the pattern is [16; 2, 6, 10, 1, 4, 1, 1, 2, 1, 2, 1, 15, …] with the block of 24 terms after the semicolon repeating forever (only the first 12 of the 24 are shown). A pattern that never ends is one more proof that √271 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
16/116.00000000004.6 × 10⁻¹
33/216.50000000003.8 × 10⁻²
214/1316.46153846155.4 × 10⁻⁴
2,173/13216.46212121214.4 × 10⁻⁵
2,387/14516.46206896558.7 × 10⁻⁶
11,721/71216.46207865171.0 × 10⁻⁶

The same fractions solve Pell’s equation, x² − 271y² = 1. Its smallest solution in positive whole numbers is x = 115,974,983,600, y = 7,044,978,537.

√271 in geometry and everyday measurements

  • A square patio or deck of 271 square feet is about 16.46 ft (16 ft 6 in) on each side, so edging all the way around takes 4 × √271 ≈ 65.8 ft.
  • 271 is not a sum of two whole-number squares — 271 is itself a prime that is one less than a multiple of 4, which rules that out — so √271 is never the diagonal of a rectangle with whole-number sides. It is not a sum of three positive squares either, so no whole-number box has √271 as its space diagonal.
RootSimplest formDecimalPerfect square?
√2682√6716.3707No
√269√26916.4012No
√2703√3016.4317No
√271√27116.4621No
√2724√1716.4924No
√273√27316.5227No
√274√27416.5529No
  • The cube root of 271 is about 6.471274.
  • Squaring undoes the root: (√271)² = 271, while 271² = 73,441 — the number whose square root is 271.

Frequently asked questions

What is the square root of 271?

The square root of 271 is √271, about 16.4620776332. The negative root, −16.462078, also squares to 271.

Is the square root of 271 rational or irrational?

Irrational. 271 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 √271 be simplified?

No. 271 is prime, so there is no perfect square to take out of the radical.

What is √271 rounded to two decimal places?

√271 ≈ 16.46 to two decimal places (16.5 to one, 16.462 to three). Check: 16.46² = 270.9316, close to 271.

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