Is 42 a prime number?
No, 42 is not a prime number. It is divisible by 2: 42 = 2 × 21.
Is 42 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 √42 ≈ 6.48. If none of them divides 42, it is prime.
- 3
2 divides 42 exactly, so it is not prime. Its prime factorisation is
LaTeX source of the formulas on this page
\[ 42 = 2 \times 3 \times 7 \]
Testing 42 by the primes up to its square root
| Prime | Division | Result |
|---|---|---|
| 2 | 42 ÷ 2 | divides exactly (21) |
| 3 | 42 ÷ 3 | divides exactly (14) |
| 5 | 42 ÷ 5 | leaves 2 |
Questions
Is 42 a prime number?
No, 42 is not a prime number. It is divisible by 2: 42 = 2 × 21.
What is the next prime after 42?
43.
What is the prime number before 42?
41.
What are the factors of 42?
1, 2, 3, 6, 7, 14, 21, 42.