| Next prime | 5 |
| Previous prime | 2 |
| Octal | (3)8 |
| Hexadecimal | (3)16 |
| Prime gap | 2 |
| 1st Twin prime (the small number) | The big number is 5 . |
| 1st Cousin prime (the small number) | The big number is 7 . |
| 1st Prime of the Form 4n+3 | |
| 1st Mersenne prime | 22 - 1 |
| 1st Fermat prime | 220 + 1 |
| 1st Euclid prime | 2 + 1 |
| 1st primorial prime | 2 + 1 |
| 2nd Factorial prime | 2! + 1 |
| 2nd Double factorial prime | 2!! + 1 |
| 2nd Sophie Germain prime | |
| 2nd Left-truncatable prime | |
| 2nd Right-truncatable prime | |
| 2nd Two-sided prime |