What is the 22nd prime number?
The 22nd prime number is 79. The next prime is 83 (a gap of 4) and the one before is 73.
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 22nd one is 79.
- 2
79 is prime because no prime up to ā79 ā 8.89 divides it.
- 3
The primes are spread thinner as numbers grow: by the prime number theorem the 22nd prime is close to 22 Ć ln(22) ā 68, and here it is 79.
- 4
79 has no twin: neither 77 nor 81 is prime.
Primes around the 22nd
| Position | Prime | Gap from the previous |
|---|---|---|
| 19 | 67 | 6 |
| 20 | 71 | 4 |
| 21 | 73 | 2 |
| 22 | 79 | 6 |
| 23 | 83 | 4 |
| 24 | 89 | 6 |
| 25 | 97 | 8 |
Questions
What is the 22nd prime number?
79.
Which prime number is 79?
79 is the 22nd prime number.
What is the sum of the first 22 primes?
791.