Back 40 (ахыԥхьаӡара) Abkhazian 40 (عدد) Arabic 40 (ədəd) Azerbaijani ۴۰ (سایی) AZB 40 (angka) BAN 40 (число) Bulgarian ༤༠ (གྲངས་ཀ།) Tibetan Quaranta Catalan 40 CDO 40 (numero) CEB
| ||||
|---|---|---|---|---|
| Cardinal | forty | |||
| Ordinal | 40th (fortieth) | |||
| Factorization | 23× 5 | |||
| Greek numeral | Μ´ | |||
| Roman numeral | XL | |||
| Binary | 1010002 | |||
| Ternary | 11113 | |||
| Quaternary | 2204 | |||
| Quinary | 1305 | |||
| Senary | 1046 | |||
| Octal | 508 | |||
| Duodecimal | 3412 | |||
| Hexadecimal | 2816 | |||
| Vigesimal | 2020 | |||
| Base 36 | 1436 | |||
40 (forty) is the number that is after thirty-nine and before forty-one.
The prime factors of forty are 2 and 5. (2 * 2 * 2 * 5 = 40)
Forty is also the only number in the English language which is spelt in alphabetical order.