What is the 991st prime number?
The 991st prime number is 7841. The next prime is 7853 (a gap of 12) and the one before is 7829.
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 991st one is 7841.
- 2
7841 is prime because no prime up to ā7841 ā 88.55 divides it.
- 3
The primes are spread thinner as numbers grow: by the prime number theorem the 991st prime is close to 991 Ć ln(991) ā 6837, and here it is 7841.
- 4
7841 has no twin: neither 7839 nor 7843 is prime.
Primes around the 991st
| Position | Prime | Gap from the previous |
|---|---|---|
| 988 | 7817 | 24 |
| 989 | 7823 | 6 |
| 990 | 7829 | 6 |
| 991 | 7841 | 12 |
| 992 | 7853 | 12 |
| 993 | 7867 | 14 |
| 994 | 7873 | 6 |
Questions
What is the 991st prime number?
7841.
Which prime number is 7841?
7841 is the 991st prime number.
What is the sum of the first 991 primes?
3,611,954.