√613 at a glance
- Exact value
- √613
- Decimal (10 places)
- 24.7588368063
- Rounded
- 24.8 · 24.76 · 24.759
- Perfect square?
- No — between 24² and 25²
- Rational?
- Irrational
- Both square roots
- ±24.758837
- Prime factorization
- 613
- Cube root
- 8.494807
How to simplify √613
613 is a prime number, so its only factors are 1 and 613. There is no perfect-square factor to pull out, which means √613 is already in its simplest radical form.
The square root of any prime is irrational. If √613 were a fraction a/b in lowest terms, then a² = 613b², so 613 would divide a — and then 613 would divide b too, contradicting “lowest terms.” That is why the decimal 24.7588368063 is only a rounded value.
Where √613 sits between perfect squares
576 = 24² and 625 = 25² are the nearest perfect squares, so √613 lies between 24 and 25. 613 is 37 above 576 and 12 below 625, so the root is closer to 25.
- Straight line between 576 and 625: 24.7551 (0.02% low)
- Tangent from 24, i.e. 24 + 37 ÷ 48: 24.7708 (0.05% high)
- Tangent from 25, i.e. 25 − 12 ÷ 50: 24.7600 (0% high)
For √613 the tangent at 25 wins, missing by only 0.0012. Tangent estimates shine when the number sits close to a perfect square — here 613 is just 12 below 625.
Finding √613 with the Babylonian method
This is Newton’s method applied to f(x) = x² − 613: following the tangent line down to zero simplifies to averaging x with 613 ÷ x.
Start from the nearest whole number, 25 (25² = 625):
| Step | Guess x | 613 ÷ x | Average | Correct decimals |
|---|---|---|---|---|
| 1 | 25.0000000000 | 24.5200000000 | 24.7600000000 | 2 |
| 2 | 24.7600000000 | 24.7576736672 | 24.7588368336 | 7 |
| 3 | 24.7588368336 | 24.7588367790 | 24.7588368063 | all 10 shown |
The count of correct decimals went 2, 7 and all 10 over 3 steps — roughly doubling each time — until the guess matched √613 = 24.7588368063 to every decimal shown.
√613 as a continued fraction
Every irrational square root has a continued fraction that repeats. For √613 the pattern is [24; 1, 3, 6, 1, 4, 1, 1, 1, 3, 2, 11, 1, …] with the block of 33 terms after the semicolon repeating forever (only the first 12 of the 33 are shown). A pattern that never ends is one more proof that √613 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 |
|---|---|---|
| 24/1 | 24.0000000000 | 7.6 × 10⁻¹ |
| 25/1 | 25.0000000000 | 2.4 × 10⁻¹ |
| 99/4 | 24.7500000000 | 8.8 × 10⁻³ |
| 619/25 | 24.7600000000 | 1.2 × 10⁻³ |
| 718/29 | 24.7586206897 | 2.2 × 10⁻⁴ |
| 3,491/141 | 24.7588652482 | 2.8 × 10⁻⁵ |
The same fractions solve Pell’s equation, x² − 613y² = 1. Its smallest solution in positive whole numbers is x = 464,018,873,584,078,278,910,994,299,849, y = 18,741,545,784,831,997,880,308,784,340 — 30 digits for x, even though 613 is small, which is what makes Pell’s equation famous. Because the period is odd, the equation with −1 on the right also has a solution: 481,673,579,088,618² − 613 × 19,454,612,624,065² = −1.
√613 in geometry and everyday measurements
- A square garage floor of 613 square feet measures about 24.76 ft (24 ft 9 in) per side, and its corner-to-corner diagonal is √1226 ≈ 35 ft.
- 613 = 17² + 18², so by the Pythagorean theorem √613 is the diagonal of a 17 × 18 rectangle — and the distance between the points (0, 0) and (17, 18) on a grid.
Square roots near √613 and related roots
| Root | Simplest form | Decimal | Perfect square? |
|---|---|---|---|
| √610 | √610 | 24.6982 | No |
| √611 | √611 | 24.7184 | No |
| √612 | 6√17 | 24.7386 | No |
| √613 | √613 | 24.7588 | No |
| √614 | √614 | 24.7790 | No |
| √615 | √615 | 24.7992 | No |
| √616 | 2√154 | 24.8193 | No |
- The cube root of 613 is about 8.494807.
- Squaring undoes the root: (√613)² = 613, while 613² = 375,769 — the number whose square root is 613.
Frequently asked questions
What is the square root of 613?
The square root of 613 is √613, about 24.7588368063. The negative root, −24.758837, also squares to 613.
Is the square root of 613 rational or irrational?
Irrational. 613 is not a perfect square — it falls between 576 and 625 — and the square root of any whole number that is not a perfect square cannot be written as a fraction.
Can √613 be simplified?
No. 613 is prime, so there is no perfect square to take out of the radical.
What is √613 rounded to two decimal places?
√613 ≈ 24.76 to two decimal places (24.8 to one, 24.759 to three). Check: 24.76² = 613.0576, close to 613.