The 2016 election had neither the highest voter turnout, nor the highest percentage of voters voting. Rebecca Harrington with a nice graph dating back to the 1700s. Some stats:
The highest overall voter turnout was 133 million Americans in the 2008 contest between Barack Obama and John McCain… While results were still trickling in, and the overall turnout could end up being higher, that preliminary total suggests that only 57% of eligible voters actually voted this year.
Trump didn’t win so much as Clinton lost. Clinton appears to have won the popular vote, while Trump didn’t fare as well as Romney did in 2012.