There is an infinite number of numbers between 0 and 20.
There are 19 numbers between zero and 365 that have an odd number of factors.
It is 10 whose factors are: 1, 2, 5 and 10
20 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.
20 number
For a number to have [only] 2 factors, it must be a prime number; the prime numbers between 0 and 20 are; 2, 3, 5, 7, 11, 13, 17, 19
1 and 5
There is an infinite number of numbers between 0 and 20.
2,3,5,7,11,13,17,19
2, 3, 5, 7, 11, 13, 17, 19
6, 8, 10, 14, 15
20
10
360
There are 19 numbers between zero and 365 that have an odd number of factors.
It is 10 whose factors are: 1, 2, 5 and 10
60,72,84,90 and 96 each have twelve factors.