Square Root of 21

What is the square root of 21?

Answer: 21 = 4.582575695
The square root of 21 is 4.582575695.
21 is not a perfect square. The square root is an irrational number.

Verification

√21 = 4.582575695

4.582575695 × 4.582575695 ≈ 21

See Also

About "Square Root Calculator" Calculator

This calculator will help you find the square root of any number. For example, it can help you find out what is the square root of 21? (The answer is: 4.582575695). Enter a number (e.g. '21') and hit the 'Calculate' button.

Square Root Table

NumberSquare RootPerfect Square
2.44949No
2.645751No
2.828427No
3Yes
3.162278No
3.316625No
3.464102No
3.605551No
3.741657No
3.872983No
4Yes
4.123106No
4.242641No
4.358899No
4.472136No
4.582576No
4.690416No
4.795832No
4.898979No
5Yes
5.09902No
5.196152No
5.291503No
5.385165No
5.477226No
5.567764No
5.656854No
5.744563No
5.830952No
5.91608No

FAQ

What is the square root of 21?

√21 = 4.582575695

Is 21 a perfect square?

No, 21 is not a perfect square because its square root is 4.582575695