All statistics are based on contigs of size >= 500 bp, unless otherwise noted (e.g., "# contigs (>= 0 bp)" and "Total length (>= 0 bp)" include all contigs).
Suggestion: all assemblies contain continuous fragments of N's of length >= 10 bp. You may consider rerunning QUAST using --scaffolds (-s) option!

Assembly   # contigs (>= 0 bp)  # contigs (>= 1000 bp)  # contigs (>= 5000 bp)  # contigs (>= 10000 bp)  # contigs (>= 25000 bp)  # contigs (>= 50000 bp)  Total length (>= 0 bp)  Total length (>= 1000 bp)  Total length (>= 5000 bp)  Total length (>= 10000 bp)  Total length (>= 25000 bp)  Total length (>= 50000 bp)  # contigs  Largest contig  Total length  GC (%)  N50     N75     L50  L75  # N's per 100 kbp
a_gigas.3  5301                 4378                    2459                    2015                     1715                     1520                     661278939               660629130                  655930236                  652842980                   648159582                   640760281                   5301       5332704         661278939     43.18   667839  332501  283  635  52.25            
nc_genome  1770                 1273                    1221                    1185                     1124                     1037                     473689068               473630402                  473505592                  473238229                   472201774                   468995938                   1295       5113825         473644963     42.61   707759  363449  193  423  49.46