Square Root of 736

The square root of 736 is 4√46 in simplest radical form, or about 27.1293199325 as a decimal.

Whole numbers, decimals or fractions like 9/16. Negative numbers have no real root.
Simplest radical form
4√46
Decimal
27.1293199325
Both real square roots
±27.1293199325x² = 736 has two real solutions
Between
27² = 729 and 28² = 784so the root is between 27 and 28
Perfect power?
No
√73627.1293199325= 4√46

Show the work

  1. Prime-factor the radicand: 736 = 25 × 23 = (24) × 2 × 23.
  2. Each pair of identical factors comes out of the radical as a single factor: √736 = 4√46.
  3. Decimal value: √736 ≈ 27.1293199325.
  4. Check: 27.12931993252 ≈ 736.

√736 at a glance

Exact value
4√46
Decimal (10 places)
27.1293199325
Rounded
27.1 · 27.13 · 27.129
Perfect square?
No — between 27² and 28²
Rational?
Irrational
Both square roots
±27.129320
Prime factorization
2⁵ × 23
Cube root
9.028715

How to simplify √736

Look for the largest perfect square that divides 736. Here it is 16 (4²), because 736 = 16 × 46 and 46 has no square factor left:

√736 = √(16 × 46) = √16 × √46 = 4√46

The prime factorization tells the same story: 736 = 2⁵ × 23. Each pair of equal primes leaves the radical as one factor, so 2² comes out and 2 × 23 stays inside.

736 has 2 square factors (4 and 16). Starting with a smaller one still works but takes more rounds: √736 = 2√184, and √184 can be simplified again. Using 16 straight away finishes in one step.

Check: (4√46)² = 4² × 46 = 16 × 46 = 736. As a decimal, 4√46 = 4 × 6.7823299831 ≈ 27.1293199325.

Where √736 sits between perfect squares

729 = 27² and 784 = 28² are the nearest perfect squares, so √736 lies between 27 and 28. 736 is 7 above 729 and 48 below 784, so the root is closer to 27.

√736 ≈ 27 + (736 − 729) ÷ (784 − 729) = 27 + 7/55 ≈ 27.1273
  • Straight line between 729 and 784: 27.1273 (0.01% low)
  • Tangent from 27, i.e. 27 + 7 ÷ 54: 27.1296 (0% high)
  • Tangent from 28, i.e. 28 − 48 ÷ 56: 27.1429 (0.05% high)

For √736 the tangent at 27 wins, missing by only 0.0003. Tangent estimates shine when the number sits close to a perfect square — here 736 is just 7 above 729.

2727² = 7292828² = 784√736 ≈ 27.1293
√736 on a number line, with tenths marked between 27 and 28.

Finding √736 with the Babylonian method

Picture a rectangle with an area of 736 and one side x; the other side must be 736 ÷ x. Averaging the two sides gives a rectangle that is closer to a square, and the side of that square is exactly √736.

xnext = (x + 736 ÷ x) ÷ 2

Start from the nearest whole number, 27 (27² = 729):

StepGuess x736 ÷ xAverageCorrect decimals
127.000000000027.259259259327.12962962963
227.129629629627.129010238927.12931993438
327.129319934327.129319930727.1293199325all 10 shown

The count of correct decimals went 3, 8 and all 10 over 3 steps — roughly doubling each time — until the guess matched √736 = 27.1293199325 to every decimal shown.

√736 as a continued fraction

Every irrational square root has a continued fraction that repeats. For √736 the pattern is [27; 7, 1, 2, 1, 2, 1, 7, 54] with the block of 8 terms after the semicolon repeating forever. A pattern that never ends is one more proof that √736 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
27/127.00000000001.3 × 10⁻¹
190/727.14285714291.4 × 10⁻²
217/827.12500000004.3 × 10⁻³
624/2327.13043478261.1 × 10⁻³
841/3127.12903225812.9 × 10⁻⁴
2,306/8527.12941176479.2 × 10⁻⁵

The same fractions solve Pell’s equation, x² − 736y² = 1. Its smallest solution in positive whole numbers is x = 24,335, y = 897.

√736 in geometry and everyday measurements

  • 736 square feet is 68.4 m². Laid out as a square — a small house footprint or a lot — it is about 27.13 ft (27 ft 2 in) on a side.
  • 736 is not a sum of two whole-number squares — the prime factor 23 (one less than a multiple of 4) appears an odd number of times, which rules that out — so √736 is never the diagonal of a rectangle with whole-number sides. It is, however, the space diagonal of a 4 × 12 × 24 box, because 4² + 12² + 24² = 736.
  • Since √736 = 4√46, a length of √736 is exactly 4 copies of the length √46 laid end to end.
RootSimplest formDecimalPerfect square?
√733√73327.0740No
√734√73427.0924No
√7357√1527.1109No
√7364√4627.1293No
√737√73727.1477No
√7383√8227.1662No
√739√73927.1846No
  • The cube root of 736 is about 9.028715.
  • Because 736 = 4 × 184, the root is twice √184: 2 × 13.56466 ≈ 27.12932.

Frequently asked questions

What is the square root of 736?

The square root of 736 is 4√46 in simplest radical form, which is about 27.1293199325. The negative root, −27.129320, also squares to 736.

Is the square root of 736 rational or irrational?

Irrational. 736 is not a perfect square — it falls between 729 and 784 — and the square root of any whole number that is not a perfect square cannot be written as a fraction.

Can √736 be simplified?

Yes. The largest perfect square dividing 736 is 16, so √736 = √16 × √46 = 4√46.

What is √736 rounded to two decimal places?

√736 ≈ 27.13 to two decimal places (27.1 to one, 27.129 to three). Check: 27.13² = 736.0369, close to 736.

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