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Mathematically, 21 is a composite number because it fails to meet the definition of a prime or neither prime nor composite number. It meets the rule for a composite number.
- Prime number - Any number whom's only two factors are one and itself, and is neither 0 nor 1, is prime.
- Composite Number - Any number with other factors than one and itself, and is neither 0 nor 1, is composite.
- Neither Composite Nor Prime - Is only 0 and 1.
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Earn +20 ptsQ: What makes 21 a composite number?
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Is 21 a prime number of composite?
21 is a composite number
What are the factors of 21 is it composite or prime?
21 is a composite number. A prime number has only 2 factors which are 1 and itself. Composite numbers are everything else except 1 and 0. 1 and 0 are neither prime, nor composite.
What is the next composite number after 20?
The next composite number after 20 is 21.
What is the composite of 21?
A composite number is a number that has more than two factors. The factors of 21 are 1, 3, 7, and 21. Therefore, 21 is a composite number.
Which is a composite number 19 21 23?
21 is composite.
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