√467 at a glance
- Exact value
- √467
- Decimal (10 places)
- 21.6101827850
- Rounded
- 21.6 · 21.61 · 21.610
- Perfect square?
- No — between 21² and 22²
- Rational?
- Irrational
- Both square roots
- ±21.610183
- Prime factorization
- 467
- Cube root
- 7.758402
How to simplify √467
467 is a prime number, so its only factors are 1 and 467. There is no perfect-square factor to pull out, which means √467 is already in its simplest radical form.
The square root of any prime is irrational. If √467 were a fraction a/b in lowest terms, then a² = 467b², so 467 would divide a — and then 467 would divide b too, contradicting “lowest terms.” That is why the decimal 21.6101827850 is only a rounded value.
Where √467 sits between perfect squares
441 = 21² and 484 = 22² are the nearest perfect squares, so √467 lies between 21 and 22. 467 is 26 above 441 and 17 below 484, so the root is closer to 22.
- Straight line between 441 and 484: 21.6047 (0.03% low)
- Tangent from 21, i.e. 21 + 26 ÷ 42: 21.6190 (0.04% high)
- Tangent from 22, i.e. 22 − 17 ÷ 44: 21.6136 (0.02% high)
For √467 the tangent at 22 wins, missing by only 0.0035. Tangent estimates shine when the number sits close to a perfect square — here 467 is just 17 below 484.
Finding √467 with the Babylonian method
If a guess is too big, 467 ÷ 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√467) in one step.
Start from the nearest whole number, 22 (22² = 484):
| Step | Guess x | 467 ÷ x | Average | Correct decimals |
|---|---|---|---|---|
| 1 | 22.0000000000 | 21.2272727273 | 21.6136363636 | 2 |
| 2 | 21.6136363636 | 21.6067297581 | 21.6101830609 | 6 |
| 3 | 21.6101830609 | 21.6101825091 | 21.6101827850 | 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 √467 = 21.6101827850 to every decimal shown.
√467 as a continued fraction
Every irrational square root has a continued fraction that repeats. For √467 the pattern is [21; 1, 1, 1, 1, 3, 3, 21, 3, 3, 1, 1, 1, …] with the block of 14 terms after the semicolon repeating forever (only the first 12 of the 14 are shown). A pattern that never ends is one more proof that √467 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 |
|---|---|---|
| 21/1 | 21.0000000000 | 6.1 × 10⁻¹ |
| 22/1 | 22.0000000000 | 3.9 × 10⁻¹ |
| 43/2 | 21.5000000000 | 1.1 × 10⁻¹ |
| 65/3 | 21.6666666667 | 5.6 × 10⁻² |
| 108/5 | 21.6000000000 | 1.0 × 10⁻² |
| 389/18 | 21.6111111111 | 9.3 × 10⁻⁴ |
The same fractions solve Pell’s equation, x² − 467y² = 1. Its smallest solution in positive whole numbers is x = 1,625,626, y = 75,225.
√467 in geometry and everyday measurements
- A square garage floor of 467 square feet measures about 21.61 ft (21 ft 7 in) per side, and its corner-to-corner diagonal is √934 ≈ 30.6 ft.
- 467 is not a sum of two whole-number squares — 467 is itself a prime that is one less than a multiple of 4, which rules that out — so √467 is never the diagonal of a rectangle with whole-number sides. It is, however, the space diagonal of a 1 × 5 × 21 box, because 1² + 5² + 21² = 467.
Square roots near √467 and related roots
| Root | Simplest form | Decimal | Perfect square? |
|---|---|---|---|
| √464 | 4√29 | 21.5407 | No |
| √465 | √465 | 21.5639 | No |
| √466 | √466 | 21.5870 | No |
| √467 | √467 | 21.6102 | No |
| √468 | 6√13 | 21.6333 | No |
| √469 | √469 | 21.6564 | No |
| √470 | √470 | 21.6795 | No |
- The cube root of 467 is about 7.758402.
- Squaring undoes the root: (√467)² = 467, while 467² = 218,089 — the number whose square root is 467.
Frequently asked questions
What is the square root of 467?
The square root of 467 is √467, about 21.6101827850. The negative root, −21.610183, also squares to 467.
Is the square root of 467 rational or irrational?
Irrational. 467 is not a perfect square — it falls between 441 and 484 — and the square root of any whole number that is not a perfect square cannot be written as a fraction.
Can √467 be simplified?
No. 467 is prime, so there is no perfect square to take out of the radical.
What is √467 rounded to two decimal places?
√467 ≈ 21.61 to two decimal places (21.6 to one, 21.610 to three). Check: 21.61² = 466.9921, close to 467.