# Prime Numbers | Factors And Multiples | Pre-Algebra | Khan Academy

What does it mean to be a prime number? Let’s progress though some whole numbers and ask ourselves if they meet the criteria. What is the criteria you ask? Watch.

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Pre-Algebra on Khan Academy: No way, this isn’t your run of the mill arithmetic. This is Pre-algebra. You’re about to play with the professionals. Think of pre-algebra as a runway. You’re the airplane and algebra is your sunny vacation destination. Without the runway you’re not going anywhere. Seriously, the foundation for all higher mathematics is laid with many of the concepts that we will introduce to you here: negative numbers, absolute value, factors, multiples, decimals, and fractions to name a few. So buckle up and move your seat into the upright position. We’re about to take off!

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## 31 thoughts

1. Fathy Atef says:

I didnt get this at all explain it in a way that most people will understand

2. allsports100 says:

Wait so only odd numbers can be prime except 2?

3. Dr. Emeter Diacope says:

I have suffered the inequalities. Your based on the equality math system. 2+3 is 5 by a degree unmeasurable or a degree of n.

4. Dr. Emeter Diacope says:

i know not related to primes, but to the constants.

5. Nick Lemke says:

Some of these “I don’t get it” comments make me lose faith in humanity.

6. taiki cho says:

this vid helped me a lot!!!!! thanks 🙂

7. Heather Smith says:

Cowboy is what I am to her. and I love her too

8. Ahmed Ali says:

Thank you so much

9. Siva Chaitanya says:

thank you now i know about prime numbers

10. The kind gamer says:

This didn’t help me

11. innertubez says:

791,159 views, that’s prime!!

12. Melissa Ramirez says:

this video helped me so much I understand prim numbers now thank you

13. Nicole Vannier says:

is 81 and 31

14. A Salaam Ash says:

thanks for the wonderful  class
just wished
the sound wasn’t soooooooooooooooooo low

15. ali ahmed with his brothers says:

so Prime numbers are only odd numbers except 2 thanks dude ite really helped

16. Marcia Aka says:

1 is not a prime number

17. Marcia Aka says:

Prime numbers are when they have 2 factors

18. minerva irizarry says:

do the freaking factor ranbow😌😌😌💩💩💩💩👍👍👍👎👌✌✋✊👊👐☝👆👇👈👉👋👏💋❤💚💋💀👤😪

19. Phoebe Chai says:

I am in in fourth grade and my mom made me a Khan academy account it is so cool

20. K says:

Loved this. Very easy to follow along. You’ve got a new subscriber.

you suck

22. Jayasinghe Rathnayake says:

Now I really know how to do prime numbers

23. Jayasinghe Rathnayake says:

You are so good at maths

24. Jayasinghe Rathnayake says:

I❤️❤️❤️❤️❤️❤️❤️❤️❤️❤️❤️❤️❤️❤️❤️❤️❤️❤️❤️❤️❤️❤️❤️❤️it

25. Ruby Angel says:

thank you… ;w;

26. Robert James Liguori says:
27. Anas Mehar says:

one how know about the editor????

28. SigNature Schrunkster says:

Negative VOTE, due to your Lousy VID!!!

29. SigNature Schrunkster says:

Sooooo, Wut is the Fucking Good in ALL this??? NOTHING!!!!!

30. Oldeuboi says:

I finally understand what prime numbers are…