| Nominal | 18921 |
| Cardinal | eighteen thousand nine hundred twenty-one |
Cardinal eighteen thousand nine hundred twenty-one | |
| Ordinal | 18,921st |
| Number of digits | 5 |
| Sum of digits | 21 |
| Product of digits | 144 |
| Number parity | Odd |
| Prime factorization | 3 x 7 x 17 x 53 |
| Prime factors | 3, 7, 17, 53 |
| Number of distinct prime factors ω(n) | 4 |
| Total number of prime factors Ω(n) | 4 |
| Sum of prime factors | 80 |
| Product of prime factors | 18921 |
| Is 18921 a prime number? | No |
| Is 18921 a semiprime number? | No |
| Is 18921 a Chen prime number? | No |
| Is 18921 a Mersenne prime number? | No |
| Is 18921 a Catalan number? | No |
| Is 18921 a Fibonacci number? | No |
| Is 18921 a Idoneal number? | No |
| Square of 18921 (n2) | 358004241 |
| Cube of 18921 (n3) | 6773798243961 |
| Square root of 18921 | 137.55362590641 |
| Natural Logarithm (ln) of 18921 | 9.8480276953318 |
| Decimal Logarithm (log) of 18921 | 4.276944085713 |
| Sine of 18921 | 0.72604480679841 |
| Cosecant of 18921 | 1.3773254634375 |
| Cosine of 18921 | -0.6876473940335 |
| Secant of 18921 | -1.4542336794652 |
| Tangent of 18921 | -1.0558388108471 |
| Cotangent of 18921 | -0.94711426566876 |
| The spelling of 18921 in words is "eighteen thousand nine hundred twenty-one", meaning that: |
| 18921 is not an aban number (as it contains the letter a) |
| 18921 is not an eban number (as it contains the letter e) |
| 18921 is not an iban number (as it contains the letter i) |
| 18921 is not an oban number (as it contains the letter o) |
| 18921 is not a tban number (as it contains the letter t) |
| 18921 is not an uban number (as it contains the letter u) |
| Bengali numerals | ১৮৯২১ |
| Eastern Arabic numerals | ١٨٬٩٢١ |
| Hieroglyphs numeralsused in Ancient Egypt | 𓂭𓆼𓆼𓆼𓆼𓆼𓆼𓆼𓆼𓍪𓎇𓏺 |
| Khmer numerals | ១៨៩២១ |
| Japanese numerals | 一万八千九百二十一 |
| Roman numerals | n/a |
| Thai numerals | ๑๘๙๒๑ |
| Arabic | ثمانية عشر ألف و تسعة مائة و واحد و عشرون |
| Croatian | osamnaest tisuća devetsto dvadeset i jedan |
| Czech | osmnáct tisíc devět set dvacet jeden |
| Danish | atten tusinde ni hundrede en og tyve |
| Dutch | achttienduizend negenhonderdéénentwintig |
| Estonian | akpe wuienyi alafa asieke blaeve vɔ ɖekɛ |
| Faroese | átjan tusin og níggjuhundraðogtjúgoein |
| Filipino | labíng-walóng libó’t siyám na daán at dalawáng pû’t isá |
| Finnish | kahdeksantoistatuhattayhdeksänsataakaksikymmentäyksi |
| French | dix-huit mille neuf cent vingt et un |
| Greek | δεκαοκτώ χίλιάδες εννιακόσια είκοσι ένα |
| German | achtzehntausendneunhunderteinundzwanzig |
| Hebrew | שמונה עשר אלף תשע מאות עשרים ואחת |
| Hindi | अठारह हज़ार नौ सौ इक्कीस |
| Hungarian | tizennyolcezerkilencszázhuszonegy |
| Icelandic | átján þúsund og níuhundrað og tuttugu og einn |
| Indonesian | delapan belas ribu sembilan ratus dua puluh satu |
| Italian | diciottomilanovecentoventuno |
| Japanese | 一万八千九百二十一 |
| Korean | 만 팔천구백이십일 |
| Latvian | astoņpadsmit tūkstoši deviņsimt divdesmit viens |
| Lithuanian | aštuoniolika tūkstančių devyni šimtai dvidešimt vienas |
| Norwegian | atten tusen ni hundre og tjueén |
| Persian | هجده هزار و نهصد و بیست و یک |
| Polish | osiemnaście tysięcy dziewięćset dwadzieścia jeden |
| Portuguese | dezoito mil novecentos e vinte e um |
| Romanian | optsprezece mii nouă sute douăzeci şi unu |
| Russian | восемнадцать тысяч девятьсот двадцать один |
| Serbian | осамнаест хиљада деветсто двадесет и један |
| Slovak | osemnásť tisíc deväťsto dvadsaťjeden |
| Slovene | asemnajst tisuću devetsto dvaset ena |
| Spanish | dieciocho mil novecientos veintiuno |
| Swahili | elfu kumi na nane, mia tisa na ishirini na moja |
| Swedish | artontusenniohundratjugoen |
| Thai | หนึ่งหมื่นแปดพันเก้าร้อยยี่สิบเอ็ด |
| Turkish | on sekiz bin dokuz yüz yirmi bir |
| Ukrainian | вісімнадцять тисяч девʼятсот двадцять один |
| Vietnamese | mười tám nghìn chín trăm hai mươi mốt |
| Number 18921 reversed | 12981 | |
| Unicode Character | U+49E9 | 䧩 |
| Unix Timestamp | Thu, 01 Jan 1970 05:15:21 +0000 | |