Step 1 :
Divide $ 982374827 $ by $ 57842515 $ and get the remainder

$$ 982374827 : 57842515 = 16 \text{ ( remainder is } \color{blue}{ 56894587 } \text{ ) } $$

The remainder is positive ($ 56894587 > 0 $), so we will continue with division.

Step 2 :
Divide $ 57842515 $ by $ \color{blue}{ 56894587 } $ and get the remainder

$$ 57842515 : 56894587 = 1 \text{ ( remainder is } \color{blue}{ 947928 } \text{ ) } $$

The remainder is still positive ($ 947928 > 0 $), so we will continue with division.

Step 3 :
Divide $ 56894587 $ by $ \color{blue}{ 947928 } $ and get the remainder

$$ 56894587 : 947928 = 60 \text{ ( remainder is } \color{blue}{ 18907 } \text{ ) } $$

The remainder is still positive ($ 18907 > 0 $), so we will continue with division.

Step 4 :
Divide $ 947928 $ by $ \color{blue}{ 18907 } $ and get the remainder

$$ 947928 : 18907 = 50 \text{ ( remainder is } \color{blue}{ 2578 } \text{ ) } $$

The remainder is still positive ($ 2578 > 0 $), so we will continue with division.

Step 5 :
Divide $ 18907 $ by $ \color{blue}{ 2578 } $ and get the remainder

$$ 18907 : 2578 = 7 \text{ ( remainder is } \color{blue}{ 861 } \text{ ) } $$

The remainder is still positive ($ 861 > 0 $), so we will continue with division.

Step 6 :
Divide $ 2578 $ by $ \color{blue}{ 861 } $ and get the remainder

$$ 2578 : 861 = 2 \text{ ( remainder is } \color{blue}{ 856 } \text{ ) } $$

The remainder is still positive ($ 856 > 0 $), so we will continue with division.

Step 7 :
Divide $ 861 $ by $ \color{blue}{ 856 } $ and get the remainder

$$ 861 : 856 = 1 \text{ ( remainder is } \color{blue}{ 5 } \text{ ) } $$

The remainder is still positive ($ 5 > 0 $), so we will continue with division.

Step 8 :
Divide $ 856 $ by $ \color{blue}{ 5 } $ and get the remainder

$$ 856 : 5 = 171 \text{ ( remainder is } \color{blue}{ 1 } \text{ ) } $$

The remainder is still positive ($ 1 > 0 $), so we will continue with division.

Step 9 :
Divide $ 5 $ by $ \color{blue}{ 1 } $ and get the remainder

$$ 5 : \color{blue}{ \boxed { 1 }} = 5 \text{ ( remainder is } \color{blue}{ 0 } \text{ ) } $$

The remainder is zero => GCD is the last divisor $ \color{blue}{ \boxed { 1 }} $.

This solution can be visualized using a Venn diagram.

The GCD equals the product of the numbers at the intersection.

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