The CAS Registry Mumber 39475-64-4 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 3,9,4,7 and 5 respectively; the second part has 2 digits, 6 and 4 respectively. Calculate Digit Verification of CAS Registry Number 39475-64: (7*3)+(6*9)+(5*4)+(4*7)+(3*5)+(2*6)+(1*4)=154 154 % 10 = 4 So 39475-64-4 is a valid CAS Registry Number.