Starting Java 8, there is support for unsigned long (unsigned 64 bits). The way you can use it is:
Long l1 = Long.parseUnsignedLong("17916881237904312345");
To print it, you can not simply print l1, but you have to first:
String l1Str = Long.toUnsignedString(l1)
Then
System.out.println(l1Str);