Is 3999 a prime number?
No, 3999 is not a prime number. It is divisible by 3: 3999 = 3 × 1333.
Is 3999 prime?
Pick any whole number from 1 to 10,000.
How to work it out
- 1
A prime number has exactly two factors: 1 and itself.
- 2
It is enough to test the primes up to √3999 ≈ 63.24. If none of them divides 3999, it is prime.
- 3
3 divides 3999 exactly, so it is not prime. Its prime factorisation is
LaTeX source of the formulas on this page
\[ 3999 = 3 \times 31 \times 43 \]
Testing 3999 by the primes up to its square root
| Prime | Division | Result |
|---|---|---|
| 2 | 3999 ÷ 2 | leaves 1 |
| 3 | 3999 ÷ 3 | divides exactly (1333) |
| 5 | 3999 ÷ 5 | leaves 4 |
| 7 | 3999 ÷ 7 | leaves 2 |
| 11 | 3999 ÷ 11 | leaves 6 |
| 13 | 3999 ÷ 13 | leaves 8 |
| 17 | 3999 ÷ 17 | leaves 4 |
| 19 | 3999 ÷ 19 | leaves 9 |
| 23 | 3999 ÷ 23 | leaves 20 |
| 29 | 3999 ÷ 29 | leaves 26 |
| 31 | 3999 ÷ 31 | divides exactly (129) |
| 37 | 3999 ÷ 37 | leaves 3 |
Questions
Is 3999 a prime number?
No, 3999 is not a prime number. It is divisible by 3: 3999 = 3 × 1333.
What is the next prime after 3999?
4001.
What is the prime number before 3999?
3989.
What are the factors of 3999?
1, 3, 31, 43, 93, 129, 1333, 3999.