Square Root of 227

The square root of 227 is about 15.0665191733. It is irrational and already in simplest form, written √227.

Whole numbers, decimals or fractions like 9/16. Negative numbers have no real root.
Simplest radical form
√227
Decimal
15.0665191733
Both real square roots
±15.0665191733x² = 227 has two real solutions
Between
15² = 225 and 16² = 256so the root is between 15 and 16
Perfect power?
No
√22715.0665191733= √227

Show the work

  1. Prime-factor the radicand: 227 = 227.
  2. No prime appears 2 or more times, so √227 is already in simplest form.
  3. Decimal value: √227 ≈ 15.0665191733.
  4. Check: 15.06651917332 ≈ 227.

√227 at a glance

Exact value
√227
Decimal (10 places)
15.0665191733
Rounded
15.1 · 15.07 · 15.067
Perfect square?
No — between 15² and 16²
Rational?
Irrational
Both square roots
±15.066519
Prime factorization
227
Cube root
6.100170

How to simplify √227

227 is a prime number, so its only factors are 1 and 227. There is no perfect-square factor to pull out, which means √227 is already in its simplest radical form.

The square root of any prime is irrational. If √227 were a fraction a/b in lowest terms, then a² = 227b², so 227 would divide a — and then 227 would divide b too, contradicting “lowest terms.” That is why the decimal 15.0665191733 is only a rounded value.

Where √227 sits between perfect squares

225 = 15² and 256 = 16² are the nearest perfect squares, so √227 lies between 15 and 16. 227 is 2 above 225 and 29 below 256, so the root is closer to 15.

√227 ≈ 15 + (227 − 225) ÷ (256 − 225) = 15 + 2/31 ≈ 15.0645
  • Straight line between 225 and 256: 15.0645 (0.01% low)
  • Tangent from 15, i.e. 15 + 2 ÷ 30: 15.0667 (0% high)
  • Tangent from 16, i.e. 16 − 29 ÷ 32: 15.0938 (0.18% high)

For √227 the tangent at 15 wins, missing by only 0.0001. Tangent estimates shine when the number sits close to a perfect square — here 227 is just 2 above 225.

1515² = 2251616² = 256√227 ≈ 15.0665
√227 on a number line, with tenths marked between 15 and 16.

Finding √227 with the Babylonian method

If a guess is too big, 227 ÷ 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√227) in one step.

xnext = (x + 227 ÷ x) ÷ 2

Start from the nearest whole number, 15 (15² = 225):

StepGuess x227 ÷ xAverageCorrect decimals
115.000000000015.133333333315.06666666673
215.066666666715.066371681415.06651917409
315.066519174015.066519172615.0665191733all 10 shown

The count of correct decimals went 3, 9 and all 10 over 3 steps — roughly doubling each time — until the guess matched √227 = 15.0665191733 to every decimal shown.

√227 as a continued fraction

Every irrational square root has a continued fraction that repeats. For √227 the pattern is [15; 15, 30] with the block of 2 terms after the semicolon repeating forever. A pattern that never ends is one more proof that √227 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
15/115.00000000006.7 × 10⁻²
226/1515.06666666671.5 × 10⁻⁴
6,795/45115.06651884703.3 × 10⁻⁷
102,151/6,78015.06651917407.2 × 10⁻¹⁰
3,071,325/203,85115.0665191733< 10⁻¹⁰
46,172,026/3,064,54515.0665191733< 10⁻¹⁰

The same fractions solve Pell’s equation, x² − 227y² = 1. Its smallest solution in positive whole numbers is x = 226, y = 15.

√227 in geometry and everyday measurements

  • A square patio or deck of 227 square feet is about 15.07 ft (15 ft 1 in) on each side, so edging all the way around takes 4 × √227 ≈ 60.3 ft.
  • 227 is not a sum of two whole-number squares — 227 is itself a prime that is one less than a multiple of 4, which rules that out — so √227 is never the diagonal of a rectangle with whole-number sides. It is, however, the space diagonal of a 1 × 1 × 15 box, because 1² + 1² + 15² = 227.
RootSimplest formDecimalPerfect square?
√2244√1414.9666No
√2251515.0000Yes
√226√22615.0333No
√227√22715.0665No
√2282√5715.0997No
√229√22915.1327No
√230√23015.1658No
  • The cube root of 227 is about 6.100170.
  • Four times the radicand doubles the root: √908 = 2 × √227 ≈ 30.133038.

Frequently asked questions

What is the square root of 227?

The square root of 227 is √227, about 15.0665191733. The negative root, −15.066519, also squares to 227.

Is the square root of 227 rational or irrational?

Irrational. 227 is not a perfect square — it falls between 225 and 256 — and the square root of any whole number that is not a perfect square cannot be written as a fraction.

Can √227 be simplified?

No. 227 is prime, so there is no perfect square to take out of the radical.

What is √227 rounded to two decimal places?

√227 ≈ 15.07 to two decimal places (15.1 to one, 15.067 to three). Check: 15.07² = 227.1049, close to 227.

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