Prime factorization of $$$1251$$$
Your Input
Find the prime factorization of $$$1251$$$.
Solution
Start with the number $$$2$$$.
Determine whether $$$1251$$$ is divisible by $$$2$$$.
Since it is not divisible, move to the next prime number.
The next prime number is $$$3$$$.
Determine whether $$$1251$$$ is divisible by $$$3$$$.
It is divisible, thus, divide $$$1251$$$ by $$${\color{green}3}$$$: $$$\frac{1251}{3} = {\color{red}417}$$$.
Determine whether $$$417$$$ is divisible by $$$3$$$.
It is divisible, thus, divide $$$417$$$ by $$${\color{green}3}$$$: $$$\frac{417}{3} = {\color{red}139}$$$.
The prime number $$${\color{green}139}$$$ has no other factors then $$$1$$$ and $$${\color{green}139}$$$: $$$\frac{139}{139} = {\color{red}1}$$$.
Since we have obtained $$$1$$$, we are done.
Now, just count the number of occurences of the divisors (green numbers), and write down the prime factorization: $$$1251 = 3^{2} \cdot 139$$$.
Answer
The prime factorization is $$$1251 = 3^{2} \cdot 139$$$A.