√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:
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.
- 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.
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.
Start from the nearest whole number, 27 (27² = 729):
| Step | Guess x | 736 ÷ x | Average | Correct decimals |
|---|---|---|---|---|
| 1 | 27.0000000000 | 27.2592592593 | 27.1296296296 | 3 |
| 2 | 27.1296296296 | 27.1290102389 | 27.1293199343 | 8 |
| 3 | 27.1293199343 | 27.1293199307 | 27.1293199325 | all 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:
| Fraction | Decimal | Error |
|---|---|---|
| 27/1 | 27.0000000000 | 1.3 × 10⁻¹ |
| 190/7 | 27.1428571429 | 1.4 × 10⁻² |
| 217/8 | 27.1250000000 | 4.3 × 10⁻³ |
| 624/23 | 27.1304347826 | 1.1 × 10⁻³ |
| 841/31 | 27.1290322581 | 2.9 × 10⁻⁴ |
| 2,306/85 | 27.1294117647 | 9.2 × 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.
Square roots near √736 and related roots
| Root | Simplest form | Decimal | Perfect square? |
|---|---|---|---|
| √733 | √733 | 27.0740 | No |
| √734 | √734 | 27.0924 | No |
| √735 | 7√15 | 27.1109 | No |
| √736 | 4√46 | 27.1293 | No |
| √737 | √737 | 27.1477 | No |
| √738 | 3√82 | 27.1662 | No |
| √739 | √739 | 27.1846 | No |
- 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.