What is the 644th prime number?
The 644th prime number is 4789. The next prime is 4793 (a gap of 4) and the one before is 4787.
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 644th one is 4789.
- 2
4789 is prime because no prime up to ā4789 ā 69.20 divides it.
- 3
The primes are spread thinner as numbers grow: by the prime number theorem the 644th prime is close to 644 Ć ln(644) ā 4165, and here it is 4789.
- 4
4789 is a twin prime: 4787 and 4789 are both prime.
Primes around the 644th
| Position | Prime | Gap from the previous |
|---|---|---|
| 641 | 4759 | 8 |
| 642 | 4783 | 24 |
| 643 | 4787 | 4 |
| 644 | 4789 | 2 |
| 645 | 4793 | 4 |
| 646 | 4799 | 6 |
| 647 | 4801 | 2 |
Questions
What is the 644th prime number?
4789.
Which prime number is 4789?
4789 is the 644th prime number.
What is the sum of the first 644 primes?
1,425,513.