Himu wrote:

no, for large numbers DEC2BIN functions dont work. Any other suggestions?

Sure it does, you just have to work a little harder.

=DEC2BIN(INT(n/256),8)&DEC2BIN(MOD(n,256),8)

However, 65536 = 2^16, so you need 17 bits to represent it, as in

=DEC2BIN(INT(n/256),9)&DEC2BIN(MOD(n,256),8)

Jerry