What is the 128th prime number?
The 128th prime number is 719. The next prime is 727 (a gap of 8) and the one before is 709.
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 128th one is 719.
- 2
719 is prime because no prime up to ā719 ā 26.81 divides it.
- 3
The primes are spread thinner as numbers grow: by the prime number theorem the 128th prime is close to 128 Ć ln(128) ā 621, and here it is 719.
- 4
719 has no twin: neither 717 nor 721 is prime.
Primes around the 128th
| Position | Prime | Gap from the previous |
|---|---|---|
| 125 | 691 | 8 |
| 126 | 701 | 10 |
| 127 | 709 | 8 |
| 128 | 719 | 10 |
| 129 | 727 | 8 |
| 130 | 733 | 6 |
| 131 | 739 | 6 |
Questions
What is the 128th prime number?
719.
Which prime number is 719?
719 is the 128th prime number.
What is the sum of the first 128 primes?
41,741.