Just for information, 1 light-year is equivalent to the distance travelled by light in 1 year moving in a vacuum. 1 light-year is about 9.4607 * 10^{15} metres.

1 astronomical unit (AU) is equivalent to the average radius of the Earth's orbit. 1 AU is about 1.4960 * 10^{11} metres.

Simple arithmetic calculation yields the answer that 1 light-year = 63240 AU to a good approximation.
Answered by:
Ryan Leong, Undergraduate, NUS, Singapore

'The mathematician's patterns, like the painter's or the poets, must be beautiful; the ideas, like the colours or the words, must fit together in a harmonious way. Beauty is the first test: there is no permanent place in the world for ugly mathematics.'