| Factorisation | 2^4 × 3 × 83 |
| Prime | no |
| Binary | 111110010000 |
| Hexadecimal | 0xF90 |
| Bit length | 12 |
| Digit sum | 24 |
| Digits spoken | three nine eight four |
3984 sits inside the sequence 2139847, beginning at digit 3 of seven.
3984 falls below the cardinality of a PubMed record, a Canadian patent application, a European patent application. Those systems assign identifiers sequentially, so it necessarily holds one in each. This is a property of the registries, not of the number. The cardinalities are published here.