7 (the 4th prime)

 
Next prime11
Previous prime5
Octal(7)8
Hexadecimal(7)16
Prime gap4
2nd Prime triplet (the smallest number)The others are 11 and 13 .
2nd Cousin prime (the small number)The big number is 11 .
2nd Sexy prime (the small number)The big number is 13 .
1st Prime of the Form 3n+122 + 3 * 12
2nd Prime of the Form 4n+3 
2nd Mersenne prime23 - 1
2nd Euclid prime3*2 + 1
3rd primorial prime3*2 + 1
4th Factorial prime3! + 1
3rd Double factorial prime4!! - 1
2nd Safe prime 
4th Left-truncatable prime 
4th Right-truncatable prime 
4th Two-sided prime