The GCD of given numbers is 227.
Step 1 : Find prime factorization of each number.
$$\begin{aligned}3567986 =& 2\cdot29\cdot227\cdot271\\[8pt]61063 =& 227\cdot269\\[8pt]\end{aligned}$$(view steps on how to factor 3567986 and 61063. )
Step 2 : Put a box around factors that are common for all numbers:
$$\begin{aligned}3567986 =& 2\cdot29\cdot\color{blue}{\boxed{227}}\cdot271\\[8pt]61063 =& \color{blue}{\boxed{227}}\cdot269\\[8pt]\end{aligned}$$Step 3 : Multiply the boxed numbers together:
$$ GCD = 227 $$This solution can be visualized using a Venn diagram.
The GCD equals the product of the numbers at the intersection.