√996 at a glance
- Exact value
- 2√249
- Decimal (10 places)
- 31.5594676761
- Rounded
- 31.6 · 31.56 · 31.559
- Perfect square?
- No — between 31² and 32²
- Rational?
- Irrational
- Both square roots
- ±31.559468
- Prime factorization
- 2² × 3 × 83
- Cube root
- 9.986649
How to simplify √996
Look for the largest perfect square that divides 996. Here it is 4 (2²), because 996 = 4 × 249 and 249 has no square factor left:
The prime factorization tells the same story: 996 = 2² × 3 × 83. Each pair of equal primes leaves the radical as one factor, so 2 comes out and 3 × 83 stays inside.
Check: (2√249)² = 2² × 249 = 4 × 249 = 996. As a decimal, 2√249 = 2 × 15.7797338381 ≈ 31.5594676761.
Where √996 sits between perfect squares
961 = 31² and 1,024 = 32² are the nearest perfect squares, so √996 lies between 31 and 32. 996 is 35 above 961 and 28 below 1,024, so the root is closer to 32.
- Straight line between 961 and 1,024: 31.5556 (0.01% low)
- Tangent from 31, i.e. 31 + 35 ÷ 62: 31.5645 (0.02% high)
- Tangent from 32, i.e. 32 − 28 ÷ 64: 31.5625 (0.01% high)
For √996 the tangent at 32 wins, missing by only 0.003. Tangent estimates shine when the number sits close to a perfect square — here 996 is just 28 below 1,024.
Finding √996 with the Babylonian method
Picture a rectangle with an area of 996 and one side x; the other side must be 996 ÷ x. Averaging the two sides gives a rectangle that is closer to a square, and the side of that square is exactly √996.
Start from the nearest whole number, 32 (32² = 1,024):
| Step | Guess x | 996 ÷ x | Average | Correct decimals |
|---|---|---|---|---|
| 1 | 32.0000000000 | 31.1250000000 | 31.5625000000 | 2 |
| 2 | 31.5625000000 | 31.5564356436 | 31.5594678218 | 6 |
| 3 | 31.5594678218 | 31.5594675305 | 31.5594676761 | all 10 shown |
The count of correct decimals went 2, 6 and all 10 over 3 steps — roughly doubling each time — until the guess matched √996 = 31.5594676761 to every decimal shown.
√996 as a continued fraction
Every irrational square root has a continued fraction that repeats. For √996 the pattern is [31; 1, 1, 3, 1, 2, 2, 1, 1, 1, 4, 1, 1, …] with the block of 20 terms after the semicolon repeating forever (only the first 12 of the 20 are shown). A pattern that never ends is one more proof that √996 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 |
|---|---|---|
| 31/1 | 31.0000000000 | 5.6 × 10⁻¹ |
| 32/1 | 32.0000000000 | 4.4 × 10⁻¹ |
| 63/2 | 31.5000000000 | 5.9 × 10⁻² |
| 221/7 | 31.5714285714 | 1.2 × 10⁻² |
| 284/9 | 31.5555555556 | 3.9 × 10⁻³ |
| 789/25 | 31.5600000000 | 5.3 × 10⁻⁴ |
The same fractions solve Pell’s equation, x² − 996y² = 1. Its smallest solution in positive whole numbers is x = 8,553,815, y = 271,038.
√996 in geometry and everyday measurements
- 996 square feet is 92.5 m². Laid out as a square — a small house footprint or a lot — it is about 31.56 ft (31 ft 7 in) on a side.
- 996 is not a sum of two whole-number squares — the prime factor 3 and 83 (one less than a multiple of 4) appears an odd number of times, which rules that out — so √996 is never the diagonal of a rectangle with whole-number sides. It is, however, the space diagonal of a 4 × 14 × 28 box, because 4² + 14² + 28² = 996.
- Since √996 = 2√249, a length of √996 is exactly 2 copies of the length √249 laid end to end.
Square roots near √996 and related roots
| Root | Simplest form | Decimal | Perfect square? |
|---|---|---|---|
| √993 | √993 | 31.5119 | No |
| √994 | √994 | 31.5278 | No |
| √995 | √995 | 31.5436 | No |
| √996 | 2√249 | 31.5595 | No |
| √997 | √997 | 31.5753 | No |
| √998 | √998 | 31.5911 | No |
| √999 | 3√111 | 31.6070 | No |
- The cube root of 996 is about 9.986649.
- Because 996 = 4 × 249, the root is twice √249: 2 × 15.779734 ≈ 31.559468.
Frequently asked questions
What is the square root of 996?
The square root of 996 is 2√249 in simplest radical form, which is about 31.5594676761. The negative root, −31.559468, also squares to 996.
Is the square root of 996 rational or irrational?
Irrational. 996 is not a perfect square — it falls between 961 and 1024 — and the square root of any whole number that is not a perfect square cannot be written as a fraction.
Can √996 be simplified?
Yes. The largest perfect square dividing 996 is 4, so √996 = √4 × √249 = 2√249.
What is √996 rounded to two decimal places?
√996 ≈ 31.56 to two decimal places (31.6 to one, 31.559 to three). Check: 31.56² = 996.0336, close to 996.