Count using accurate descriptors

[Pinkie]

What does "accurate descriptors" mean? Well, say something about the number without using digits. Like this for 1:

The only number that isn't prime or composite.

 

[Occasionally Returns]

2. The only whole number between 1 and 3

 

[Princess Céline]

3. the first odd prime number, and the second smallest prime number.

 

[Occasionally Returns]

4. Two 2s

 

[Smg2daisy]

The number of regular convex polyhedrons in three dimensions.

 

[Princess Céline]

6 is the only even perfect number that is not the sum of successive odd cubes

 

[NathanBros]

7. The fourth prime number.

 

[Princess Céline]

8, the first number which is neither prime nor semiprime.

 

[NathanBros]

Nine is the highest single-digit number in the decimal system.

 

[Princess Céline]

10, the first binary digit number.

 

[Krizzy]

11, the highest number of inches under a foot.

 

[Princess Céline]

12, it can be divided by 2, 3, 4 and 6.

 

[Krizzy]

The number that comes to mind the most easily when you hear "unlucky number", in western countries.