221540-42-7 Usage
Check Digit Verification of cas no
The CAS Registry Mumber 221540-42-7 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 2,2,1,5,4 and 0 respectively; the second part has 2 digits, 4 and 2 respectively.
Calculate Digit Verification of CAS Registry Number 221540-42:
(8*2)+(7*2)+(6*1)+(5*5)+(4*4)+(3*0)+(2*4)+(1*2)=87
87 % 10 = 7
So 221540-42-7 is a valid CAS Registry Number.