The CAS Registry Mumber 57536-47-7 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 5,7,5,3 and 6 respectively; the second part has 2 digits, 4 and 7 respectively. Calculate Digit Verification of CAS Registry Number 57536-47: (7*5)+(6*7)+(5*5)+(4*3)+(3*6)+(2*4)+(1*7)=147 147 % 10 = 7 So 57536-47-7 is a valid CAS Registry Number.