What is the 122nd prime number?
The 122nd prime number is 673. The next prime is 677 (a gap of 4) and the one before is 661.
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 122nd one is 673.
- 2
673 is prime because no prime up to ā673 ā 25.94 divides it.
- 3
The primes are spread thinner as numbers grow: by the prime number theorem the 122nd prime is close to 122 Ć ln(122) ā 586, and here it is 673.
- 4
673 has no twin: neither 671 nor 675 is prime.
Primes around the 122nd
| Position | Prime | Gap from the previous |
|---|---|---|
| 119 | 653 | 6 |
| 120 | 659 | 6 |
| 121 | 661 | 2 |
| 122 | 673 | 12 |
| 123 | 677 | 4 |
| 124 | 683 | 6 |
| 125 | 691 | 8 |
Questions
What is the 122nd prime number?
673.
Which prime number is 673?
673 is the 122nd prime number.
What is the sum of the first 122 primes?
37,561.