√837 at a glance
- Exact value
- 3√93
- Decimal (10 places)
- 28.9309522830
- Rounded
- 28.9 · 28.93 · 28.931
- Perfect square?
- No — between 28² and 29²
- Rational?
- Irrational
- Both square roots
- ±28.930952
- Prime factorization
- 3³ × 31
- Cube root
- 9.424142
How to simplify √837
Look for the largest perfect square that divides 837. Here it is 9 (3²), because 837 = 9 × 93 and 93 has no square factor left:
The prime factorization tells the same story: 837 = 3³ × 31. Each pair of equal primes leaves the radical as one factor, so 3 comes out and 3 × 31 stays inside.
Check: (3√93)² = 3² × 93 = 9 × 93 = 837. As a decimal, 3√93 = 3 × 9.643650761 ≈ 28.9309522830.
Where √837 sits between perfect squares
784 = 28² and 841 = 29² are the nearest perfect squares, so √837 lies between 28 and 29. 837 is 53 above 784 and 4 below 841, so the root is closer to 29.
- Straight line between 784 and 841: 28.9298 (0% low)
- Tangent from 28, i.e. 28 + 53 ÷ 56: 28.9464 (0.05% high)
- Tangent from 29, i.e. 29 − 4 ÷ 58: 28.9310 (0% high)
For √837 the tangent at 29 wins, missing by only 0.0001. Tangent estimates shine when the number sits close to a perfect square — here 837 is just 4 below 841.
Finding √837 with the Babylonian method
This is Newton’s method applied to f(x) = x² − 837: following the tangent line down to zero simplifies to averaging x with 837 ÷ x.
Start from the nearest whole number, 29 (29² = 841):
| Step | Guess x | 837 ÷ x | Average | Correct decimals |
|---|---|---|---|---|
| 1 | 29.0000000000 | 28.8620689655 | 28.9310344828 | 4 |
| 2 | 28.9310344828 | 28.9308700834 | 28.9309522831 | 9 |
| 3 | 28.9309522831 | 28.9309522829 | 28.9309522830 | all 10 shown |
The count of correct decimals went 4, 9 and all 10 over 3 steps — roughly doubling each time — until the guess matched √837 = 28.9309522830 to every decimal shown.
√837 as a continued fraction
Every irrational square root has a continued fraction that repeats. For √837 the pattern is [28; 1, 13, 2, 13, 1, 56] with the block of 6 terms after the semicolon repeating forever. A pattern that never ends is one more proof that √837 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 |
|---|---|---|
| 28/1 | 28.0000000000 | 9.3 × 10⁻¹ |
| 29/1 | 29.0000000000 | 6.9 × 10⁻² |
| 405/14 | 28.9285714286 | 2.4 × 10⁻³ |
| 839/29 | 28.9310344828 | 8.2 × 10⁻⁵ |
| 11,312/391 | 28.9309462916 | 6.0 × 10⁻⁶ |
| 12,151/420 | 28.9309523810 | 9.8 × 10⁻⁸ |
The same fractions solve Pell’s equation, x² − 837y² = 1. Its smallest solution in positive whole numbers is x = 12,151, y = 420.
√837 in geometry and everyday measurements
- 837 square feet is 77.8 m². Laid out as a square — a small house footprint or a lot — it is about 28.93 ft (28 ft 11 in) on a side.
- 837 is not a sum of two whole-number squares — the prime factor 3 and 31 (one less than a multiple of 4) appears an odd number of times, which rules that out — so √837 is never the diagonal of a rectangle with whole-number sides. It is, however, the space diagonal of a 2 × 7 × 28 box, because 2² + 7² + 28² = 837.
- Since √837 = 3√93, a length of √837 is exactly 3 copies of the length √93 laid end to end.
Square roots near √837 and related roots
| Root | Simplest form | Decimal | Perfect square? |
|---|---|---|---|
| √834 | √834 | 28.8791 | No |
| √835 | √835 | 28.8964 | No |
| √836 | 2√209 | 28.9137 | No |
| √837 | 3√93 | 28.9310 | No |
| √838 | √838 | 28.9482 | No |
| √839 | √839 | 28.9655 | No |
| √840 | 2√210 | 28.9828 | No |
- The cube root of 837 is about 9.424142.
- Squaring undoes the root: (√837)² = 837, while 837² = 700,569 — the number whose square root is 837.
Frequently asked questions
What is the square root of 837?
The square root of 837 is 3√93 in simplest radical form, which is about 28.9309522830. The negative root, −28.930952, also squares to 837.
Is the square root of 837 rational or irrational?
Irrational. 837 is not a perfect square — it falls between 784 and 841 — and the square root of any whole number that is not a perfect square cannot be written as a fraction.
Can √837 be simplified?
Yes. The largest perfect square dividing 837 is 9, so √837 = √9 × √93 = 3√93.
What is √837 rounded to two decimal places?
√837 ≈ 28.93 to two decimal places (28.9 to one, 28.931 to three). Check: 28.93² = 836.9449, close to 837.