The CAS Registry Mumber 1036509-32-6 includes 10 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 7 digits, 1,0,3,6,5,0 and 9 respectively; the second part has 2 digits, 3 and 2 respectively. Calculate Digit Verification of CAS Registry Number 1036509-32: (9*1)+(8*0)+(7*3)+(6*6)+(5*5)+(4*0)+(3*9)+(2*3)+(1*2)=126 126 % 10 = 6 So 1036509-32-6 is a valid CAS Registry Number.