Number

1,904

1,904 is a composite number, even, a calendar year.

1,904 (one thousand nine hundred four) is an even 4-digit number. It is a composite number with 20 divisors, and factors as 2⁴ × 7 × 17. Its proper divisors sum to 2,560, more than the number itself, making it an abundant number. Written other ways, in Roman numerals it is MCMIV and in binary, 11101110000.

Abundant Number Evil Number Gapful Number Harshad / Niven Practical Number Recamán's Sequence Semiperfect Number Year

Interestingness

★ ★ ★ ☆ ☆

5 notable facts · grade C

1,892 1,893 1,894 1,895 1,896 1,897 1,898 1,899 1,900 1,901 1,902 1,903 1,904 1,905 1,906 1,907 1,908 1,909 1,910 1,911 1,912 1,913 1,914 1,915 1,916

less more

Notable events — 1904 AD

Feb 8 Japan attacks Russian-held Port Arthur, beginning the Russo-Japanese War.
Apr 8 Britain and France sign the Entente Cordiale.
Apr 30 The Louisiana Purchase Exposition opens in St. Louis.
Jul 21 The Trans-Siberian Railway is completed.
Oct 27 The first underground line of the New York subway opens.

Events compiled from Wikipedia ↗ · Licensed CC BY-SA 4.0

Year facts

Year type: Leap year
Divisible by 4 and not by 100; February has 29 days.
Days in year: 366
ISO weeks: 52
Started on: Friday
January 1, 1904
Ended on: Saturday
December 31, 1904
Friday the 13ths: 1
One Friday the 13th this year.
Easter Sunday: April 3
Sunday, April 3, 1904
Decade: 1900s
1900–1909
Century: 20th century
1901–2000
Millennium: 2nd millennium
1001–2000
Years ago: 122
122 years before 2026.
US presidential election: Yes
US holds a presidential election in years divisible by 4 starting from 1788.
Summer Olympics: Yes

In other calendars

Hebrew: 5664 / 5665 AM
Rosh Hashanah falls in September/October.
Islamic Hijri: 1321 / 1322 AH
Lunar calendar; year spans differ from Gregorian.
Chinese: Year of the zodiac:Wood zodiac:Dragon
Sexagenary cycle position 41 of 60. Lunar new year falls in late January / mid-February.
Buddhist Era: 2447 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
Persian Solar Hijri: 1282 / 1283 SH
Iranian calendar; Nowruz (new year) falls on the spring equinox.
Ethiopian: 1896 / 1897 ET
Year boundary at Enkutatash (September 11/12).
Indian National (Saka): 1826 / 1825 Saka
Indian national calendar; year starts in March.
Japanese: Meiji 37
Reign-era counting from the start of each emperor's reign.

Properties

Parity: Even
Digit count: 4
Digit sum: 14
Digit product: 0
Digital root: 5
Palindrome: No
Bit width: 11 bits
Reversed: 4,091
Recamán's sequence: a(7,936) = 1,904
Square (n²): 3,625,216
Cube (n³): 6,902,411,264
Divisor count: 20
σ(n) — sum of divisors: 4,464
φ(n) — Euler's totient: 768
Sum of prime factors: 32

Primality

Prime factorization: 2 ⁴ × 7 × 17

Nearest primes: 1,901 (−3) · 1,907 (+3)

Divisors & multiples

All divisors (20)

1 · 2 · 4 · 7 · 8 · 14 · 16 · 17 · 28 · 34 · 56 · 68 · 112 · 119 · 136 · 238 · 272 · 476 · 952 (half) · 1904

Aliquot sum (sum of proper divisors): 2,560

Factor pairs (a × b = 1,904)

1 × 1904

2 × 952

4 × 476

7 × 272

8 × 238

14 × 136

16 × 119

17 × 112

28 × 68

34 × 56

First multiples

1,904 · 3,808 (double) · 5,712 · 7,616 · 9,520 · 11,424 · 13,328 · 15,232 · 17,136 · 19,040

Sums & aliquot sequence

As consecutive integers: 269 + 270 + … + 275 104 + 105 + … + 120 44 + 45 + … + 75

Aliquot sequence: 1,904 → 2,560 → 3,578 → 1,792 → 2,296 → 2,744 → 3,256 → 3,584 → 4,600 → 6,560 → 9,316 → 8,072 → 7,078 → 3,542 → 3,370 → 2,714 → 1,606 — unresolved within range

Continued fraction of √n

√1,904 = [43; (1, 1, 1, 2, 1, 4, 1, 2, 1, 1, 1, 86)]

Period length 12 — the block in parentheses repeats forever.

Representations

In words: one thousand nine hundred four
Ordinal: 1904th
Roman numeral: MCMIV
Binary: 11101110000
Octal: 3560
Hexadecimal: 0x770
Base64: B3A=
One's complement: 63,631 (16-bit)
Scientific notation: 1.904 × 10³
As a duration: 1,904 s = 31 minutes, 44 seconds

In other bases

ternary (3) 2121112

quaternary (4) 131300

quinary (5) 30104

senary (6) 12452

septenary (7) 5360

nonary (9) 2545

undecimal (11) 1481

duodecimal (12) 1128

tridecimal (13) b36

tetradecimal (14) 9a0

pentadecimal (15) 86e

As an angle

1,904° = 5 × 360° + 104°

104° ≈ 1.815 rad

Compass bearing: ESE (east-southeast)

Why does a circle have 360 degrees? →

Historical numeral systems

Babylonian (base 60): 𒌋𒌋𒌋𒁹 𒌋𒌋𒌋𒌋𒁹𒁹𒁹𒁹
Egyptian hieroglyphic: 𓆼𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓏺𓏺𓏺𓏺
Greek (Milesian): ͵αϡδʹ
Mayan (base 20): 𝋤·𝋯·𝋤
Chinese: 一千九百零四
Chinese (financial): 壹仟玖佰零肆

In other modern scripts

Eastern Arabic ١٩٠٤ Devanagari १९०४ Bengali ১৯০৪ Tamil ௧௯௦௪ Thai ๑๙๐๔ Tibetan ༡༩༠༤ Khmer ១៩០៤ Lao ໑໙໐໔ Burmese ၁၉၀၄

Digit at this position in famous constants

π — Pi (π): Digit 1,904 = 7
e — Euler's number (e): Digit 1,904 = 7
φ — Golden ratio (φ): Digit 1,904 = 1
√2 — Pythagoras's (√2): Digit 1,904 = 2
ln 2 — Natural log of 2: Digit 1,904 = 2
γ — Euler-Mascheroni (γ): Digit 1,904 = 2

Also seen as

Goldbach decomposition

Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 1904, here are decompositions:

3 + 1901 = 1904
31 + 1873 = 1904
37 + 1867 = 1904
43 + 1861 = 1904
73 + 1831 = 1904
103 + 1801 = 1904
127 + 1777 = 1904
151 + 1753 = 1904

Showing the first eight; more decompositions exist.

Unicode codepoint

Arabic Letter Seen With Small Arabic Letter Tah And Two Dots

U+0770

Other letter (Lo)

UTF-8 encoding: DD B0 (2 bytes).

Lookup U+0770 on Compart ↗ Lookup on FileFormat.Info ↗

Hex color

#000770

RGB(0, 7, 112)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.7.112.

Address: 0.0.7.112
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.7.112

Unspecified address (0.0.0.0/8) — "this network" placeholder.

Musical pitch

Heard as a frequency, 1,904 Hz is closest to:

Concert pitch (A4 = 440 Hz): A♯6 (1864.7 Hz, +36¢)
Scientific pitch (C4 = 256 Hz): B6 (1933.1 Hz, -26¢)
Baroque pitch (A4 = 415 Hz): B6 (1863.3 Hz, +37¢)

Position in π

The digit sequence 1904 first appears in π at position 22,867 of the decimal expansion (the 22,867ordinal-suffix:th digit after the integer 3).

Search range: the first 1,000,000 fractional digits of π. Any 6-digit-or-shorter string is virtually guaranteed to appear in there — the more interesting signal is the position.

Look up 1904 on Pi Search ↗