Multi finger transistor layout...

I have designed a folded cascode opamp in which i'am using transistors of W=400um,l=1um; w=313um, l=1um; w=278um,l=1um.....

If i need to draw the layout of these transistors say of width w=400um and length l=1um as multifingers, how many fingers can i use....
can i use
(i) w=20 um and 20 fingers for w=400um for a channel length of 1um
(ii) w=39um and 8 fingers for w=313um for L=1um
(iii) w=28um and 10 fingers for w=278um and L=1um....


One more doubt is
Since my length is 1um and i'am using a lambda value(in layout) as 0.25 for 0.35um process technology, my length can be scaled to 4 units in grid.... min. width for polysilicon layer is 2 lambda.... so for a length of 1um, i could use only 2 fingers.... each of 2 lambda units making 4 lambda, so when i extracted in spice, i got the correct w/l ratio....
is my thinking correct...

or is there no relation between the length and the fingers.....

Please help.....Thanks in advance

Finger width is not relative to lamda.

I mean the length and the no. of fingers.....

The length is not relative to the finger number if all fingers are paralleled.
If fingers are series connected, the length will be summed.