191 is a prime number from 101-200. 191 has 2 factors, 1 and 191. It is the 43rd prime number, and the eighteenth prime number from 101-200.
As an Exponent of Mersenne Number
2191 - 1 is divisible by number such as 383 and 7,068,569,257, and is therefore not a prime number.
Relationship with other odd numbers
The numbers before
- The previous prime number is 181.
- Notably, 187 is not a prime number. It can be factored as 11 x 17.
- The previous prime number before 181 is 179.
The numbers after
- The next prime number is 193.
- There are no odd numbers between 191 and 193. As a result, they are twin primes.
- 197 is the next prime number after 193.
- 191 and 197 are six numbers apart; therefore, they are sexy primes.