What is the 4th prime number?
The 4th prime number is 7. The next prime is 11 (a gap of 4) and the one before is 5.
Position
Pick any whole number from 1 to 10,000.
How to work it out
- 1
List the primes in order: 2, 3, 5, 7, 11, 13, ā¦ The 4th one is 7.
- 2
7 is prime because no prime up to ā7 ā 2.65 divides it.
- 3
The primes are spread thinner as numbers grow: by the prime number theorem the 4th prime is close to 4 Ć ln(4) ā 6.
- 4
7 is a twin prime: 5 and 7 are both prime.
Primes around the 4th
| Position | Prime | Gap from the previous |
|---|---|---|
| 1 | 2 | - |
| 2 | 3 | 1 |
| 3 | 5 | 2 |
| 4 | 7 | 2 |
| 5 | 11 | 4 |
| 6 | 13 | 2 |
| 7 | 17 | 4 |
Questions
What is the 4th prime number?
7.
Which prime number is 7?
7 is the 4th prime number.
What is the sum of the first 4 primes?
17.