• Math and Arithmetic

Is 21 a square number?

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Answered 2010-02-22 21:34:33

21 is not the square of an integer. The closest square number is 25.

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Is number 21 a square number?


How do you find the square of 21?

To square a number, you multiply it by itself. In this case, 21 x 21 is 441

Is 21 a square number itself?


What are the square root of 21?

The square roots of 21 are 4.5826 (rounded) and the negative of the same number.

What is an Adam number?

If the reverse square root of the reverse of square of a number is the number itself then it is Adam Number. For ex., 12 and 21 Take 12 square of 12 = 144 reverse of square of 12 = 441 square root of the reverse of square of 12 = 21 The reverse square root of the reverse of square of 12 = 12, then number itself. Such number is called Adam Number. cool....................

Is 21 a perfert square?

Square Number: A number that is a product of some integer with itself. Therefore, 21 is not a perfect square. An example of a perfect square is 16, since 4 times 4 is 16.

Is the square root of 21 a rational number?

No. The square root of an integer is either an integer, or an irrational number.

What square number can be taken away from 100 to make 21?

There is no such number.

Is the square root of 84 a rational number?

No because it is 2 times the square root of 21 which is an irrational numberThe square root of 84 is not a rational number

What is the whole number of 84 square feet?


Is the square root of 21 a real number?

Yes, albeit an irrational number

Is 444 a square number?

No, 441 is though (it is 21 squared)

Is the square root of 21 an irrational or a rational number?


How many square feet in a 21' x 21' room?

21*21 = 441 square feet.21*21 = 441 square feet.21*21 = 441 square feet.21*21 = 441 square feet.

What is the smallest number that can be multiplied by 147 so that the answer must be a square number?

your answer is 3 147 * 3 = 441 21 * 21 = 441

What number can you square and get a answer between 400 and 450?

The answer is 21. 21 X 21=441 and that's between 400 and 450

When you subtract 1 square number from another the answer is 21 what are the 2 squared numbers?

They are: 25-4 = 21

What is the square root of 84 simplify?

It is: 2 times the square root of 21 and it's an irrational number

What 2 square number subtract to make 21?


What is the least number to be added to 1500 to make it a perfect square?


Is the number 21 composite square or prime?

21 is a composite number because it has at least one positive factor other than one or itself.

What is the square of 21?

the square of 21 is 441

What number is a square and triangle number?

36 is both a square number and a triangle number as it is:6x6=36andthe square numbers are:1, 3, 6, 10, 15, 21, 28, 36, 45,55, 66, 78.xx

Which number between 20 and 40 is both a triangular number and a square number 36 or 25 or 21 or 35?

36 is the only square number that is also a triangular number between 20 and 40.

When you subtract a square numbers with another square number you get 21 what are the two numbers?

25 and 4 or 121 and 100