Given your example, this will display the number as TEXT

=TEXT(A1*10^6,"000000000000000")

If you want it numeric, multiple by 10^6 (10 to power 6) and
Format=custom=000000000000000

HTH

"pm" wrote:

I need to format numeric - decimal 9.0
size 15

i.e. 1.50 = 000000001500000

Thanks.