## FANDOM

836 Pages

43 is a prime number from 1-100. 43 has 2 factors, 1 and 43. It is the fourteenth prime number, and the fourteenth prime number from 1-100. ## Proofs

• Therefore, 43 has two factors.

## As an Exponent of Mersenne Number

243 - 1, which is the number 8,796,093,022,207, is divisible by numbers such as 431 and 9,719, and therefore not a prime number.

## Relationship with other odd numbers

### The numbers before

• The previous odd number, 41, is a prime number.
• There are no odd numbers between 41 and 43. As a result, they are twin primes.
• The previous odd number, 39, is not a prime number. It is divisible by 3 and 11.
• The odd number previous to 39 is 37. 37 is a prime number.
• 37 and 43 are six numbers apart; therefore, they are sexy primes.

### The numbers after

• The next odd number, 45, is not a prime number. It is divisible by 5 and 9.
• 47, the odd number following 45, is a prime number.
• 43 and 47 are four numbers apart; therefore, they are cousin primes.
• 49, the odd number following 47, is not a prime number. It is the square number, being 72 = 49.
Community content is available under CC-BY-SA unless otherwise noted.