What is the 7991st prime number?
The 7991st prime number is 81701. The next prime is 81703 (a gap of 2) and the one before is 81689.
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 7991st one is 81701.
- 2
81701 is prime because no prime up to ā81701 ā 285.83 divides it.
- 3
The primes are spread thinner as numbers grow: by the prime number theorem the 7991st prime is close to 7991 Ć ln(7991) ā 71808, and here it is 81701.
- 4
81701 is a twin prime: 81701 and 81703 are both prime.
Primes around the 7991st
| Position | Prime | Gap from the previous |
|---|---|---|
| 7988 | 81671 | 4 |
| 7989 | 81677 | 6 |
| 7990 | 81689 | 12 |
| 7991 | 81701 | 12 |
| 7992 | 81703 | 2 |
| 7993 | 81707 | 4 |
| 7994 | 81727 | 20 |
Questions
What is the 7991st prime number?
81701.
Which prime number is 81701?
81701 is the 7991st prime number.
What is the sum of the first 7991 primes?
308,941,616.