Is 6 a prime number?
6 is not a prime number, because it is divisible by 2: 6 = 2 × 3, and it has 4 factors.
Checking 6 for primality, divisor by divisor
| Try | Into | Gives | Verdict |
|---|---|---|---|
| 2 | 6 | 3 remainder 0 | divides exactly |
You only need to test primes up to the square root of 6, about 2: if 6 had a factor bigger than that, its partner would be smaller and would already have been found.
The quick checks first
- Divisible by 2? Yes: the last digit is even.
- Divisible by 3? Yes: the digit sum is 6.
- Divisible by 5? No: the last digit is 6.
- Divisible by 9? No: the digit sum is 6.
- Divisible by 10? No: the last digit is 6.
All the factors of 6
1, 2, 3, 6 (4 factors)
Prime factorisation: 2 × 3.
The primes near 6
The prime before 6 is 5; the prime after it is 7.
🧮 Calculator
The answer appears here, with the working in words.
✏️ Five questions, answers hidden
1. Is 7 prime?
Answer: yes
2. Is 8 prime?
Answer: no
3. What is the smallest prime factor of 10?
Answer: 2
4. List the primes between 10 and 30.
Answer: 11, 13, 17, 19, 23, 29
5. Up to which number do you need to test divisors for 19?
Answer: the square root, about 4
📚 The class this belongs to
Prime and composite numbers are taught in Grade 4 and 5 in the US, Year 5 in the UK (KS2), Class 5 and 6 in CBSE and Year 5 and 6 in Australia.
If this page is the homework and the method is not sticking, that is what a 1-on-1 class fixes: one tutor with a master's degree, one child, on a shared whiteboard, in your time zone, about US$10 to $13 an hour. How 1-on-1 online tutoring works.