1187.40   725.79     4.04    -7.51  0103753  0913
1363.31   724.57     0.00     0.00  0103754  0913
 564.34   725.77     0.00     0.00  0103755  0913
1174.40   726.31     0.00     0.00  0103756  0913
 527.56   728.31    -3.82     1.38  0103757  0913
 543.29   727.94    -0.80     0.24  0103758  0913
1510.04   729.10     0.00     0.00  0103760  0913
1565.91   738.97     1.80     1.37  0103762  0913
. . .

input = Import["data.txt", "Table"];

8*8918347*6 Bytes = 428080656 Bytes = 408.35 MB