The GCD of given numbers is 17.
Step 1 : Find prime factorization of each number.
$$\begin{aligned}3587 =& 17\cdot211\\[8pt]697 =& 17\cdot41\\[8pt]\end{aligned}$$(view steps on how to factor 3587 and 697. )
Step 2 : Put a box around factors that are common for all numbers:
$$\begin{aligned}3587 =& \color{blue}{\boxed{17}}\cdot211\\[8pt]697 =& \color{blue}{\boxed{17}}\cdot41\\[8pt]\end{aligned}$$Step 3 : Multiply the boxed numbers together:
$$ GCD = 17 $$This solution can be visualized using a Venn diagram.
The GCD equals the product of the numbers at the intersection.