3 is a prime number from 1-100. 3 is prime because it only has 2 factors, 1 and 3. It is said to be the first odd prime, because the previous prime number is 2, which is even. It is the second prime number, and the second prime number from 1-100.
- It is divisible by 1: 3/1=3
- It is not divisible by 2: 3/2=1.5
- It is divisible by 3: 3/3=1
- Therefore it has 2 factors, not 3, because 3 cannot be divided by 2.
Relationship with other odd numbers
The numbers before
- 2 is the first prime number. It is the only even prime number.
- 1, the number before 2, is not a prime number.
The numbers after
- The next odd number, 5, is a prime number.
- There are no odd numbers between 3 and 5. As a result, they are twin primes.
- 7, the odd number following 5, is a prime number.
- 3 and 7 are four numbers apart, therefore, they are cousin primes.
- 9, the odd number following 7, is not a prime number. It is a square number, and the first odd composite number.