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1 It's an integer which is a whole number
2 It's an odd number
3 It's not divisible by 2 with no remainder
4 It's a perfect square when multiplied by itself
5 Its square root is an irrational number
6 It's a rational number
7 It's 21/1 expressed as a fraction
8 It's 21.0 expressed as a decimal
9 Its digital sum is 3
10 It's a composite number
11 Its prime factors are 3 and 7
12 Its composite factor is itself
13 It has 1 as a factor which is neither a prime or a composite number
14 It becomes 1 when raised to the power of zero
15 It remains the same when raised to the power of 1
16 It can form the perimeter of an equilateral triangle
17 It's 2.1*10^1 in scientific notation
18 Its equivalent fraction is 42/2
19 It's the sum of the dots on a dice
20 It belongs to the Hindu-Arabic numeral system
21 Its equivalent Roman number is XXI
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What are two mathematical facts about the number 21?
It is an odd number. It is not prime. Its factors are 1, 3, 7 and 21. It is positive.
What math facts about the number 21?
It is a triangular number In Roman numerals = XXI It is the sun of the first 6 numbers (1+2+3+4+5+6=21)
Why is 21 a composite number?
21 is composite number because it has more than one number that goes into it
What is 5 more than one third of a number is -2?
7
Is 21 a prime or composite number?
21 is a Composite Number. A prime number is a whole number that only has two factors which are itself and one. A composite number has factors in addition to one and itself. 21 is divisible by 3 and 7.
What are two mathematical facts about the number 21?
It is an odd number. It is not prime. Its factors are 1, 3, 7 and 21. It is positive.
What are some trivial fact for 21?
Here are some trivial facts about the number 21, there is a game named 21, Sammy Sosa's jersey was 21, 21 is the age of adulthood.
What is 13-21?
13-21 = -8
What is 90 percent of 21 questions?
90% of 21 = 18.9So, in order to score 90% on a test with 21 questions,you can't miss more than two of them.
What math facts about the number 21?
It is a triangular number In Roman numerals = XXI It is the sun of the first 6 numbers (1+2+3+4+5+6=21)
Why is 21 a composite number?
21 is composite number because it has more than one number that goes into it
What is the 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.
What is a high score on the OCI-R?
There is a reccomended cut-off score of 21. When you score higher tan 21 it means a presence of OCD
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.
What are three mathematical facts about the number 20?
It is the successor of 19. It is the predecessor of 21. It is two time ten.
What are facts about 21?
21 is a composite number, which means that is can be divided by numbers other than 1 and 21 into another whole number. It can be divided by 3 and 7. The best (not highest) number of points in a game of Blackjack is 21. We are now living in the 21st century. In roman numerals, 21 = XXI, where X is ten and I is 1.
What number has more factors than 21?
The number 21 has only four factors: 1, 3, 7, and 21. Many number have more than four factors. Among them are 1x2x3x4x5 = 120.
