Help, display more than 20 digits on 7 segments

Other Hardware LEDs and Multiplexing
2

You can only fit 19 decimal digits on 16 hex characters
0xEfff ffff ffff ffff = 9,223,372,036,854,775,807
If you had 0xffff ffff ffff ffff ULL that would be 18,446,744,073,709,551,614 - still just 20 digits