Number

1,813

1,813 is a composite number, odd, a calendar year.

Arithmetic Number Deficient Number Evil Number Recamán's Sequence Year

Notable events — 1813 AD

Jun 21 Wellington defeats the French at Vitoria, all but ending French power in Spain.
Oct 19 Napoleon is defeated at the Battle of Leipzig (Battle of the Nations).
Oct 5 Shawnee leader Tecumseh is killed at the Battle of the Thames.
Sep 10 Oliver Hazard Perry defeats the British squadron on Lake Erie.
Jan 28 Jane Austen publishes Pride and Prejudice.

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: Friday
January 1, 1813
Ended on: Friday
December 31, 1813
Friday the 13ths: 1
One Friday the 13th this year.
Easter Sunday: April 18
Sunday, April 18, 1813
Decade: 1810s
1810–1819
Century: 19th century
1801–1900
Millennium: 2nd millennium
1001–2000
Years ago: 213
213 years before 2026.

In other calendars

Hebrew: 5573 / 5574 AM
Rosh Hashanah falls in September/October.
Islamic Hijri: 1227 / 1229 AH
Lunar calendar; year spans differ from Gregorian.
Chinese: Year of the zodiac:Water zodiac:Rooster
Sexagenary cycle position 10 of 60. Lunar new year falls in late January / mid-February.
Buddhist Era: 2356 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
Persian Solar Hijri: 1191 / 1192 SH
Iranian calendar; Nowruz (new year) falls on the spring equinox.
Ethiopian: 1805 / 1806 ET
Year boundary at Enkutatash (September 11/12).
Indian National (Saka): 1735 / 1734 Saka
Indian national calendar; year starts in March.

Properties

Parity: Odd
Digit count: 4
Digit sum: 13
Digit product: 24
Digital root: 4
Palindrome: No
Bit width: 11 bits
Reversed: 3,181
Recamán's sequence: a(16,073) = 1,813
Square (n²): 3,286,969
Cube (n³): 5,959,274,797
Divisor count: 6
σ(n) — sum of divisors: 2,166
φ(n) — Euler's totient: 1,512
Sum of prime factors: 51

Primality

Prime factorization: 7 ² × 37

Nearest primes: 1,811 (−2) · 1,823 (+10)

Divisors & multiples

All divisors (6)

1 · 7 · 37 · 49 · 259 · 1813

Aliquot sum (sum of proper divisors): 353

Factor pairs (a × b = 1,813)

1 × 1813

7 × 259

37 × 49

First multiples

1,813 · 3,626 (double) · 5,439 · 7,252 · 9,065 · 10,878 · 12,691 · 14,504 · 16,317 · 18,130

Sums & aliquot sequence

As a sum of two squares: 7² + 42²

As consecutive integers: 906 + 907 256 + 257 + … + 262 123 + 124 + … + 136 31 + 32 + … + 67

Aliquot sequence: 1,813 → 353 → 1 → 0 — terminates at zero

Representations

In words: one thousand eight hundred thirteen
Ordinal: 1813th
Roman numeral: MDCCCXIII
Binary: 11100010101
Octal: 3425
Hexadecimal: 0x715
Base64: BxU=
One's complement: 63,722 (16-bit)

In other bases

ternary (3) 2111011

quaternary (4) 130111

quinary (5) 24223

senary (6) 12221

septenary (7) 5200

nonary (9) 2434

undecimal (11) 13a9

duodecimal (12) 1071

tridecimal (13) a96

tetradecimal (14) 937

pentadecimal (15) 80d

Historical numeral systems

Babylonian (base 60): 𒌋𒌋𒌋 𒌋𒁹𒁹𒁹
Egyptian hieroglyphic: 𓆼𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓎆𓏺𓏺𓏺
Greek (Milesian): ͵αωιγʹ
Mayan (base 20): 𝋤·𝋪·𝋭
Chinese: 一千八百一十三
Chinese (financial): 壹仟捌佰壹拾參

In other modern scripts

Eastern Arabic ١٨١٣ Devanagari १८१३ Bengali ১৮১৩ Tamil ௧௮௧௩ Thai ๑๘๑๓ Tibetan ༡༨༡༣ Khmer ១៨១៣ Lao ໑໘໑໓ Burmese ၁၈၁၃

Digit at this position in famous constants

π — Pi (π): Digit 1,813 = 1
e — Euler's number (e): Digit 1,813 = 2
φ — Golden ratio (φ): Digit 1,813 = 4
√2 — Pythagoras's (√2): Digit 1,813 = 7
ln 2 — Natural log of 2: Digit 1,813 = 6
γ — Euler-Mascheroni (γ): Digit 1,813 = 1

Also seen as

Unicode codepoint

Syriac Letter Dalath

U+0715

Other letter (Lo)

UTF-8 encoding: DC 95 (2 bytes).

Lookup U+0715 on Compart ↗ Lookup on FileFormat.Info ↗

Hex color

#000715

RGB(0, 7, 21)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.7.21.

Address: 0.0.7.21
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.7.21

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

Position in π

The digit sequence 1813 first appears in π at position 5,510 of the decimal expansion (the 5,510ordinal-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 1813 on Pi Search ↗