2871000000 km to au conversion result above is displayed in three different forms: as a decimal (which could be rounded), in scientific notation (scientific form, standard index form or standard form in the United Kingdom) and as a fraction (exact result). Every display form has its own advantages and in different situations particular form is more convenient than another. For example usage of scientific notation when working with big numbers is recommended due to easier reading and comprehension. Usage of fractions is recommended when more precision is needed.
If we want to calculate how many Astronomical Units are 2871000000 Kilometers we have to multiply 2871000000 by 10 and divide the product by 1495978707. So for 2871000000 we have: (2871000000 × 10) ÷ 1495978707 = 28710000000 ÷ 1495978707 = 19.191449628033 Astronomical Units
So finally 2871000000 km = 19.191449628033 au