Of those odd numbers, only 57 is composite.
15 is a composite number - it can be divided by 3 and 5. 11, 13, 17 and 19 are all prime numbers, not composite.
2 is an even prime number. 3, 7, 11, 13 are odd prime numbers.
Just multiply two or more odd prime numbers, for example: 3 x 3 = 9 7 x 11 x 13 = 1001
None of the numbers 7, 11, and 13 are composite numbers; they are all primes.
There are infinitely many odd numbers that are prime. Take any set of odd numbers greater than 1. Their product will be odd and, by definition, it will be composite. For example, 3*5*13 = 195.
Composite. It is divisible by 11 and 13.
Composite. (2 * 11 * 13 = 286)
143 is not prime. 143 = 11 * 13
12
1573 is not prime. 1573 = 11 * 11 * 13. Thus, it is a composite number.
Composite numbers can have either an odd number or an even number of fractions. Factors of 25 are 1, 5, 25 . (odd number of them) Factors of 26 are 1, 2, 13, and 26 . (even number of them)
11 x 13 = 143, making it composite.