√20421 = 142.902064
The square root of 20421 is 142.902064. Free square root calculator with 10 decimal precision.
√20421 = 142.902064. Verified: 142.902064 x 142.902064 ≈ 20421.
How This Was Calculated
The square root of a number x is the value that, multiplied by itself, gives x:
sqrt(x) x sqrt(x) = x
The nth root generalizes this: nth root of x = x^(1/n). Square roots of non-perfect squares are irrational numbers with non-repeating decimal expansions.
Quick Reference Table
| Input | Result |
|---|---|
| 20416 | 142.884569 |
| 20419 | 142.895066 |
| 20420 | 142.898565 |
| 20422 | 142.905563 |
| 20423 | 142.909062 |
| 20426 | 142.919558 |
Frequently Asked Questions
What is a square root?
The square root of a number is the value that, when multiplied by itself, equals the original number. For example, the square root of 25 is 5 because 5 x 5 = 25.
What is a perfect square?
A perfect square is a number whose square root is a whole number, like 1, 4, 9, 16, 25, 36, 49, 64, 81, 100, 121, 144, and so on.
Can you take the square root of a negative number?
Not in real numbers. The square root of a negative number is imaginary — for example, sqrt(-9) = 3i, where i is the imaginary unit.
How do I estimate a square root manually?
Find the two perfect squares it sits between. For sqrt(50): 49 (7^2) and 64 (8^2), so the answer is between 7 and 8, closer to 7. Actual: 7.071.
What is the square root of 2?
The square root of 2 is approximately 1.4142135624. It is an irrational number, meaning its decimal expansion never ends or repeats.