The percentage of nitrogen in urea is about 46.6%.

Explanation:
The chemical formula of urea is as follows:
Urea = NH₂​CONH₂​
Molar mass of Urea is = 60.06 g/mol

Mass of Nitrogen = 14.006 gms
And there are 2 atoms of nitrogen.

So, percentage of nitrogen in urea = ((2 * 14.006)/60.06) * 100 = 46.6%