If 4.22 x 10^24 oxygen atoms are in a container containing sodium sulphate what is the mass of sodium sulphate

I divided 4.22x10^24 by 4 because there are 4 oxygen atoms in sodium sulphate. Then i multiplied it by the molar mass.
(4.22 x 10^24)/4=1.055 x 10^24

(1.055 x 10^24) x 142.045 = 1.5 x 10^26

i dont know if i did this right :/

units Na2SO4 = (4.22*10^24 atoms O) * (1 unit Na2SO4 / 4 atoms O) = 1.055*10^24 units Na2SO4

mass Na2SO4 = (1.055 units Na2SO4) * (1 mol Na2SO4 / 6.02*10^23 units Na2SO4) * (142.04 grams Na2SO4 / 1 mol Na2SO4) = 248.92 grams Na2SO4 is the answer.