I found the divisibility conditions of four sides a, b, c and d in a primitive 4d euler brick (if exists):
1. One is divided by 64, another by 16, another by 4, another odd.
2. One is divided by 27, another by 9, another by 3, another not by 3.
3. Two is divided by 5.
4. Two is divided by 11.
5. One is divided by 13.
6. One is divided by 19.

## Divisibility

I found the divisibility conditions of four sides a, b, c and d in a primitive 4d euler brick (if exists):

1. One is divided by 64, another by 16, another by 4, another odd.

2. One is divided by 27, another by 9, another by 3, another not by 3.

3. Two is divided by 5.

4. Two is divided by 11.

5. One is divided by 13.

6. One is divided by 19.