i am a number between 7 000 000 and 8 000 000 all my digits are odd all the digits in my thousands period are the same all the digits in my units period are the same the sum of my digits is 31 what number am i ?

69,420

7 777 111, 7 555 333, 7 111 777

234444444444444444444444444

7,333,555

7 333 555

7 555 333
7 777 111
7 111 777

733 333 333

7 135 7911