21111-57-9 Usage
Check Digit Verification of cas no
The CAS Registry Mumber 21111-57-9 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 2,1,1,1 and 1 respectively; the second part has 2 digits, 5 and 7 respectively.
Calculate Digit Verification of CAS Registry Number 21111-57:
(7*2)+(6*1)+(5*1)+(4*1)+(3*1)+(2*5)+(1*7)=49
49 % 10 = 9
So 21111-57-9 is a valid CAS Registry Number.