Adding an l to make an int a long does not run when doing multiplication.

I am trying to do some multiplication in a drool.

long grace = 30l/days/ * 24 * 60 * 60 * 1000;

But, when it runs I get the error: 'Operator ";" expected' I can however do.

long grace1 = 30;
long grace2 = 24;
long grace3 = 60;
long grace4 = 1000;
long grace = grace1 * grace2 * grace3 * grace3 * grace4;