Is 138 a prime number?
No, 138 is not a prime number. It is divisible by 2: 138 = 2 × 69.
Is 138 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 √138 ≈ 11.75. If none of them divides 138, it is prime.
- 3
2 divides 138 exactly, so it is not prime. Its prime factorisation is
LaTeX source of the formulas on this page
\[ 138 = 2 \times 3 \times 23 \]
Testing 138 by the primes up to its square root
| Prime | Division | Result |
|---|---|---|
| 2 | 138 ÷ 2 | divides exactly (69) |
| 3 | 138 ÷ 3 | divides exactly (46) |
| 5 | 138 ÷ 5 | leaves 3 |
| 7 | 138 ÷ 7 | leaves 5 |
| 11 | 138 ÷ 11 | leaves 6 |
Questions
Is 138 a prime number?
No, 138 is not a prime number. It is divisible by 2: 138 = 2 × 69.
What is the next prime after 138?
139.
What is the prime number before 138?
137.
What are the factors of 138?
1, 2, 3, 6, 23, 46, 69, 138.