| Nominal | 3999 |
| Cardinal | three thousand nine hundred ninety-nine |
Cardinal three thousand nine hundred ninety-nine | |
| Ordinal | 3,999th |
| Number of digits | 4 |
| Sum of digits | 30 |
| Product of digits | 2187 |
| Number parity | Odd |
| Prime factorization | 3 x 31 x 43 |
| Prime factors | 3, 31, 43 |
| Number of distinct prime factors ω(n) | 3 |
| Total number of prime factors Ω(n) | 3 |
| Sum of prime factors | 77 |
| Product of prime factors | 3999 |
| Is 3999 a prime number? | No |
| Is 3999 a semiprime number? | No |
| Is 3999 a Chen prime number? | No |
| Is 3999 a Mersenne prime number? | No |
| Is 3999 a Catalan number? | No |
| Is 3999 a Fibonacci number? | No |
| Is 3999 a Idoneal number? | No |
| Square of 3999 (n2) | 15992001 |
| Cube of 3999 (n3) | 63952011999 |
| Square root of 3999 | 63.23764701505 |
| Natural Logarithm (ln) of 3999 | 8.2937996088468 |
| Decimal Logarithm (log) of 3999 | 3.6019514041335 |
| Sine of 3999 | 0.24493051100782 |
| Cosecant of 3999 | 4.0827906490101 |
| Cosine of 3999 | -0.96954063595986 |
| Secant of 3999 | -1.0314162840735 |
| Tangent of 3999 | -0.25262531751992 |
| Cotangent of 3999 | -3.9584314423322 |
| The spelling of 3999 in words is "three thousand nine hundred ninety-nine", meaning that: |
| 3999 is not an aban number (as it contains the letter a) |
| 3999 is not an eban number (as it contains the letter e) |
| 3999 is not an iban number (as it contains the letter i) |
| 3999 is not an oban number (as it contains the letter o) |
| 3999 is not a tban number (as it contains the letter t) |
| 3999 is not an uban number (as it contains the letter u) |
| Bengali numerals | ৩৯৯৯ |
| Eastern Arabic numerals | ٣٬٩٩٩ |
| Hieroglyphs numeralsused in Ancient Egypt | 𓆼𓆼𓆼𓍪𓎎𓐂 |
| Khmer numerals | ៣៩៩៩ |
| Japanese numerals | 三千九百九十九 |
| Roman numerals | MMMCMXCIX |
| Thai numerals | ๓๙๙๙ |
| Arabic | ثلاثة آلاف و تسعة مائة و تسعة و تسعون |
| Croatian | tri tisuće devetsto devedeset i devet |
| Czech | tři tisíce devět set devadesát devět |
| Danish | tre tusinde ni hundrede ni og halvfems |
| Dutch | drieduizend negenhonderdnegenennegentig |
| Estonian | akpe etɔ̃ alafa asieke blaasieke vɔ asieke |
| Faroese | trý tusin og níggjuhundraðognítiníggju |
| Filipino | tatlóng libó’t siyám na daán at siyám na pû’t siyám |
| Finnish | kolmetuhattayhdeksänsataayhdeksänkymmentäyhdeksän |
| French | trois mille neuf cent quatre-vingt-dix-neuf |
| Greek | τρεις χίλιάδες εννιακόσια εννενήντα εννέα |
| German | dreitausendneunhundertneunundneunzig |
| Hebrew | שלושת אלפים תשע מאות תשעים ותשע |
| Hindi | तीन हज़ार नौ सौ निन्यानबे |
| Hungarian | háromezerkilencszázkilencvenkilenc |
| Icelandic | þrjú þúsund og níuhundrað og níutíu og níu |
| Indonesian | tiga ribu sembilan ratus sembilan puluh sembilan |
| Italian | tremilanovecentonovantanove |
| Japanese | 三千九百九十九 |
| Korean | 삼천구백구십구 |
| Latvian | trīstūkstoš deviņsimt deviņdesmit deviņi |
| Lithuanian | trys tūkstančiai devyni šimtai devyniasdešimt devyni |
| Norwegian | tre tusen ni hundre og nittini |
| Persian | سه هزار و نهصد و نود و نه |
| Polish | trzy tysiące dziewięćset dziewięćdziesiąt dziewięć |
| Portuguese | três mil novecentos e noventa e nove |
| Romanian | trei mii nouă sute nouăzeci şi nouă |
| Russian | три тысячи девятьсот девяносто девять |
| Serbian | три хиљада деветсто деведесет и девет |
| Slovak | tri tisíc deväťsto deväťdesiatdeväť |
| Slovene | tri tisuće devetsto devetdeset devet |
| Spanish | tres mil novecientos noventa y nueve |
| Swahili | elfu tatu, mia tisa na tisini na tisa |
| Swedish | tretusenniohundranittionio |
| Thai | สามพันเก้าร้อยเก้าสิบเก้า |
| Turkish | üç bin dokuz yüz doksan dokuz |
| Ukrainian | три тисячі девʼятсот девʼяносто девʼять |
| Vietnamese | ba nghìn chín trăm chín mươi chín |
| Number 3999 reversed | 9993 | |
| Unicode Character | U+0F9F | ྟ |
| Unix Timestamp | Thu, 01 Jan 1970 01:06:39 +0000 | |