You can only trust what was given to you as 69 nano moles of stuff per 1 ml.
If you have 1 ml of the stuff, and 69 nano moles in it, you then have 69 nano moles * avagrados number of molecules
Avagrados # is
# of "stuff"
And in this case, the "stuff" is molecules. Avagrados number is just like a dozen, just a number. You can have a dozen eggs or a dozen waffles.
But remember Avagrados number is in mols, so you must convert nano mols to mols first.