The CAS Registry Mumber 107596-45-2 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,0,7,5,9 and 6 respectively; the second part has 2 digits, 4 and 5 respectively. Calculate Digit Verification of CAS Registry Number 107596-45: (8*1)+(7*0)+(6*7)+(5*5)+(4*9)+(3*6)+(2*4)+(1*5)=142 142 % 10 = 2 So 107596-45-2 is a valid CAS Registry Number.