The CAS Registry Mumber 1372549-74-0 includes 10 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 7 digits, 1,3,7,2,5,4 and 9 respectively; the second part has 2 digits, 7 and 4 respectively. Calculate Digit Verification of CAS Registry Number 1372549-74: (9*1)+(8*3)+(7*7)+(6*2)+(5*5)+(4*4)+(3*9)+(2*7)+(1*4)=180 180 % 10 = 0 So 1372549-74-0 is a valid CAS Registry Number.