Number

1,913

1,913 is a prime, odd, a calendar year.

1,913 (one thousand nine hundred thirteen) is an odd 4-digit number. It is a prime number — divisible only by 1 and itself. Written other ways, in Roman numerals it is MCMXIII and in binary, 11101111001.

Arithmetic Number Chen Prime Cube-Free Deficient Number Emirp Evil Number Prime Pythagorean Prime Recamán's Sequence Sexy Prime Squarefree Year

Interestingness

★ ★ ★ ★ ★

9 notable facts · grade A

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 1,917 1,918 1,919 1,920 1,921 1,922 1,923 1,924 1,925

less more

Notable events — 1913 AD

Feb 3 The 16th Amendment authorizes a federal income tax in the US.
Mar 4 Woodrow Wilson is inaugurated as US president.
May 29 Stravinsky's Rite of Spring premieres in Paris, sparking a near-riot.
Oct 7 Henry Ford introduces the moving assembly line at his Highland Park plant.
Dec 23 The Federal Reserve Act creates the US central bank.

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

Year facts

Year type: Common year
Standard 365-day year; not divisible by 4 (or divisible by 100 but not 400).
Days in year: 365
ISO weeks: 52
Started on: Wednesday
January 1, 1913
Ended on: Wednesday
December 31, 1913
Friday the 13ths: 1
One Friday the 13th this year.
Easter Sunday: March 23
Sunday, March 23, 1913
Decade: 1910s
1910–1919
Century: 20th century
1901–2000
Millennium: 2nd millennium
1001–2000
Years ago: 113
113 years before 2026.

In other calendars

Hebrew: 5673 / 5674 AM
Rosh Hashanah falls in September/October.
Islamic Hijri: 1331 / 1332 AH
Lunar calendar; year spans differ from Gregorian.
Chinese: Year of the zodiac:Water zodiac:Ox
Sexagenary cycle position 50 of 60. Lunar new year falls in late January / mid-February.
Buddhist Era: 2456 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
Persian Solar Hijri: 1291 / 1292 SH
Iranian calendar; Nowruz (new year) falls on the spring equinox.
Ethiopian: 1905 / 1906 ET
Year boundary at Enkutatash (September 11/12).
Indian National (Saka): 1835 / 1834 Saka
Indian national calendar; year starts in March.
Japanese: Taishō 2
Reign-era counting from the start of each emperor's reign.

Properties

Parity: Odd
Digit count: 4
Digit sum: 14
Digit product: 27
Digital root: 5
Palindrome: No
Bit width: 11 bits
Reversed: 3,191
Recamán's sequence: a(7,918) = 1,913
Square (n²): 3,659,569
Cube (n³): 7,000,755,497
Divisor count: 2
σ(n) — sum of divisors: 1,914
φ(n) — Euler's totient: 1,912

Primality

1,913 is prime. It has exactly two divisors: 1 and itself.

Divisors & multiples

All divisors (2)

1 · 1913

Aliquot sum (sum of proper divisors): 1

Factor pairs (a × b = 1,913)

1 × 1913

First multiples

1,913 · 3,826 (double) · 5,739 · 7,652 · 9,565 · 11,478 · 13,391 · 15,304 · 17,217 · 19,130

Sums & aliquot sequence

As a sum of two squares: 8² + 43²

As consecutive integers: 956 + 957

Continued fraction of √n

√1,913 = [43; (1, 2, 1, 4, 2, 1, 1, 10, 2, 1, 11, 1, 4, 1, 1, 4, 1, 11, 1, 2, 10, 1, 1, 2, …)]

Period length 29 — the block in parentheses repeats forever.

Representations

In words: one thousand nine hundred thirteen
Ordinal: 1913th
Roman numeral: MCMXIII
Binary: 11101111001
Octal: 3571
Hexadecimal: 0x779
Base64: B3k=
One's complement: 63,622 (16-bit)
Scientific notation: 1.913 × 10³
As a duration: 1,913 s = 31 minutes, 53 seconds

In other bases

ternary (3) 2121212

quaternary (4) 131321

quinary (5) 30123

senary (6) 12505

septenary (7) 5402

nonary (9) 2555

undecimal (11) 148a

duodecimal (12) 1135

tridecimal (13) b42

tetradecimal (14) 9a9

pentadecimal (15) 878

Palindromic in base 3, base 14, base 15

As an angle

1,913° = 5 × 360° + 113°

113° ≈ 1.972 rad

Compass bearing: ESE (east-southeast)

Why does a circle have 360 degrees? →

Historical numeral systems

Babylonian (base 60): 𒌋𒌋𒌋𒁹 𒌋𒌋𒌋𒌋𒌋𒁹𒁹𒁹
Egyptian hieroglyphic: 𓆼𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓎆𓏺𓏺𓏺
Greek (Milesian): ͵αϡιγʹ
Mayan (base 20): 𝋤·𝋯·𝋭
Chinese: 一千九百一十三
Chinese (financial): 壹仟玖佰壹拾參

In other modern scripts

Eastern Arabic ١٩١٣ Devanagari १९१३ Bengali ১৯১৩ Tamil ௧௯௧௩ Thai ๑๙๑๓ Tibetan ༡༩༡༣ Khmer ១៩១៣ Lao ໑໙໑໓ Burmese ၁၉၁၃

Digit at this position in famous constants

π — Pi (π): Digit 1,913 = 0
e — Euler's number (e): Digit 1,913 = 4
φ — Golden ratio (φ): Digit 1,913 = 4
√2 — Pythagoras's (√2): Digit 1,913 = 0
ln 2 — Natural log of 2: Digit 1,913 = 1
γ — Euler-Mascheroni (γ): Digit 1,913 = 9

Also seen as

Prime neighborhood

Adjacent primes:

Previous prime: 1,907 (gap of 6)
Next prime: 1,931 (gap of 18)

Pair status: sexy with 1907.

Unicode codepoint

Arabic Letter Waw With Extended Arabic-Indic Digit Three Above

U+0779

Other letter (Lo)

UTF-8 encoding: DD B9 (2 bytes).

Lookup U+0779 on Compart ↗ Lookup on FileFormat.Info ↗

Hex color

#000779

RGB(0, 7, 121)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.7.121.

Address: 0.0.7.121
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.7.121

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

Musical pitch

Heard as a frequency, 1,913 Hz is closest to:

Concert pitch (A4 = 440 Hz): A♯6 (1864.7 Hz, +44¢)
Scientific pitch (C4 = 256 Hz): B6 (1933.1 Hz, -18¢)
Baroque pitch (A4 = 415 Hz): B6 (1863.3 Hz, +46¢ — about midway to C7)

Position in π

The digit sequence 1913 first appears in π at position 3,826 of the decimal expansion (the 3,826ordinal-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 1913 on Pi Search ↗