If you wanted to measure a cell, it would be something (not enen close, just example) like this
4.253246 X 10^-43
You are right about not being close. Your number is about 10 quadrillion times smaller than an electron when the unit distance is a light-year. Electron width in light-years =1.057e-31 Lys
Planck length is the smallest measurement of length with any meaning. Aprox. equal to 1.6 x 10-35 m