LCID
The LCID (28 Bit) includes the CellID and the RNC.
CID
The CID is 16 Bit.
Calculate the LCID with the value RNC and CID
(65536 * RNC) + CID = LCID
Example:
(65536 * 504) + 6287 = 33036431
Calculate the CID with the value LCID
Mod(LCID/65636) = CID