The CAS Registry Mumber 74602-62-3 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 7,4,6,0 and 2 respectively; the second part has 2 digits, 6 and 2 respectively. Calculate Digit Verification of CAS Registry Number 74602-62: (7*7)+(6*4)+(5*6)+(4*0)+(3*2)+(2*6)+(1*2)=123 123 % 10 = 3 So 74602-62-3 is a valid CAS Registry Number.