I don't see why we can't extend $duration to have some other formats. I'll list the current formats, for comparison purposes.

Format: $duration(seconds,N)
Examples below are for 2910912809213 seconds

N = 1: 4813017wks 1day 11hrs 26mins 53secs
N = 2: 4813017wks 1day 11hrs 26mins
N = 3: 808586891:26:53

My suggestions below
N = 4: 33691120days 11hrs 26mins 53secs
N = 5: 33691120days 11hrs 26mins
N = 6: 33691120:11:26:53