The CAS Registry Mumber 1439436-85-7 includes 10 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 7 digits, 1,4,3,9,4,3 and 6 respectively; the second part has 2 digits, 8 and 5 respectively. Calculate Digit Verification of CAS Registry Number 1439436-85: (9*1)+(8*4)+(7*3)+(6*9)+(5*4)+(4*3)+(3*6)+(2*8)+(1*5)=187 187 % 10 = 7 So 1439436-85-7 is a valid CAS Registry Number.