Use a Caterpillar!
Count the days and calculate them
In Earth days t would take a huge number because in Earth years it is 164.79!
The rotation of the planet Neptune is much faster than Earth's. It completes a rotational "day" in about 16 Earth hours. So in an Earth year (365.25 Earth days), Neptune completes about 544 Neptune days. In a Neptune year, there are about 89,666 Neptune days.
Neptune has 60,190 number of days in a year.
60,190.03 Earth days (164.79 Earth years) (89,666 Neptune days)
Neptune takes about 165 Earth years to orbit around the sun once. This means Neptune's year is equal to approximately 165 Earth years.
One orbit for Neptune takes nearly 165 Earth years (164.79 years). This is approximately 60,190 Earth days. But a day (complete rotation) for Neptune is much shorter than Earth's, about 16 Earth hours. So there are about 89,666 "Neptune days" in a "Neptune year".
Neptune orbits the sun, not Earth. Its orbital period is 60,182 Earth days, or about 165 Earth years.
Neptune takes 16.1 hours to make a full rotation, which is equivalent to 0.673 Earth days.
14366400 earth days will it take to complete its revolution
It would take over 16,000 Earth days, or around 44 Earth years, for a spacecraft to travel from Earth to Neptune at its average distance from Earth. The actual time would depend on the speed and trajectory of the spacecraft.
I image you are asking the age in terms of Neptune years or days. The Neptune year is about 164 earth years and each Neptune solar year is made of about 89666 Neptune solar days. This means that a Neptune solar day has a duration of about 1.5 earth days. Since January the first of year 2000, 4295 earth solar days are elapsed up to October 4 2012. This means that a person that was born on the earth on the first day of year 2000, when it is October 4 2012 on earth has an age of about 2863 Neptune days. They correspond to about 0.031 Neptune solar years, but the fact has to be considered that no man lives a whole Neptune year :-)