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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)

Q: What math facts about the number 21?

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It is the 6th prime number.

26 = 64

composite even deficient

The number 11 is a prime number and it`s factors are 1 and 11

2 + 2 = 4. This is a fact.It is the first prime number.

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its a number!!

It is the 6th prime number.

It is composite

26 = 64

its an integer its a whole number it is not a prime number....

composite even deficient

The number 11 is a prime number and it`s factors are 1 and 11

It is the answer to the ultimate question of life, the universe, and everything.

2 + 2 = 4. This is a fact.It is the first prime number.

Since 13 is a prime number, the only factors that it has are 1 and 13.

It is an odd number. It is not prime. Its factors are 1, 3, 7 and 21. It is positive.

27 is a cube, meaning that it is the product of a number cubed, which in this instance is 3.