The CAS Registry Mumber 60171-38-2 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 6,0,1,7 and 1 respectively; the second part has 2 digits, 3 and 8 respectively. Calculate Digit Verification of CAS Registry Number 60171-38: (7*6)+(6*0)+(5*1)+(4*7)+(3*1)+(2*3)+(1*8)=92 92 % 10 = 2 So 60171-38-2 is a valid CAS Registry Number.