Number

1,979

1,979 is a prime, odd, a calendar year.

1,979 (one thousand nine hundred seventy-nine) 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 MCMLXXIX and in binary, 11110111011.

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

Interestingness

★ ★ ★ ★ ★

8 notable facts · grade A

1,967 1,968 1,969 1,970 1,971 1,972 1,973 1,974 1,975 1,976 1,977 1,978 1,979 1,980 1,981 1,982 1,983 1,984 1,985 1,986 1,987 1,988 1,989 1,990 1,991

less more

Notable events — 1979 AD

Jan 16 The Shah flees Iran amid revolution; Khomeini returns from exile two weeks later.
Mar 28 A partial meltdown at Three Mile Island becomes the worst US nuclear accident.
May 4 Margaret Thatcher becomes the UK's first female prime minister.
Nov 4 Iranian students seize the US embassy in Tehran; 52 Americans are held hostage.
Dec 24 Soviet forces invade Afghanistan, beginning a nine-year war.

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: Monday
January 1, 1979
Ended on: Monday
December 31, 1979
Friday the 13ths: 2
2 Friday the 13ths this year.
Easter Sunday: April 15
Sunday, April 15, 1979
Decade: 1970s
1970–1979
Century: 20th century
1901–2000
Millennium: 2nd millennium
1001–2000
Years ago: 47
47 years before 2026.

In other calendars

Hebrew: 5739 / 5740 AM
Rosh Hashanah falls in September/October.
Islamic Hijri: 1399 / 1400 AH
Lunar calendar; year spans differ from Gregorian.
Chinese: Year of the zodiac:Earth zodiac:Goat
Sexagenary cycle position 56 of 60. Lunar new year falls in late January / mid-February.
Buddhist Era: 2522 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
Persian Solar Hijri: 1357 / 1358 SH
Iranian calendar; Nowruz (new year) falls on the spring equinox.
Ethiopian: 1971 / 1972 ET
Year boundary at Enkutatash (September 11/12).
Indian National (Saka): 1901 / 1900 Saka
Indian national calendar; year starts in March.
Japanese: Shōwa 54
Reign-era counting from the start of each emperor's reign.

Properties

Parity: Odd
Digit count: 4
Digit sum: 26
Digit product: 567
Digital root: 8
Palindrome: No
Bit width: 11 bits
Reversed: 9,791
Recamán's sequence: a(3,793) = 1,979
Square (n²): 3,916,441
Cube (n³): 7,750,636,739
Divisor count: 2
σ(n) — sum of divisors: 1,980
φ(n) — Euler's totient: 1,978

Primality

1,979 is prime. It has exactly two divisors: 1 and itself.

Divisors & multiples

All divisors (2)

1 · 1979

Aliquot sum (sum of proper divisors): 1

Factor pairs (a × b = 1,979)

1 × 1979

First multiples

1,979 · 3,958 (double) · 5,937 · 7,916 · 9,895 · 11,874 · 13,853 · 15,832 · 17,811 · 19,790

Sums & aliquot sequence

As consecutive integers: 989 + 990

Continued fraction of √n

√1,979 = [44; (2, 17, 3, 2, 1, 2, 1, 6, 8, 1, 2, 1, 43, 1, 2, 1, 8, 6, 1, 2, 1, 2, 3, 17, …)]

Period length 26 — the block in parentheses repeats forever.

Representations

In words: one thousand nine hundred seventy-nine
Ordinal: 1979th
Roman numeral: MCMLXXIX
Binary: 11110111011
Octal: 3673
Hexadecimal: 0x7BB
Base64: B7s=
One's complement: 63,556 (16-bit)
Scientific notation: 1.979 × 10³
As a duration: 1,979 s = 32 minutes, 59 seconds

In other bases

ternary (3) 2201022

quaternary (4) 132323

quinary (5) 30404

senary (6) 13055

septenary (7) 5525

nonary (9) 2638

undecimal (11) 153a

duodecimal (12) 118b

tridecimal (13) b93

tetradecimal (14) a15

pentadecimal (15) 8be

Palindromic in base 3

As an angle

1,979° = 5 × 360° + 179°

179° ≈ 3.124 rad

Compass bearing: S (south)

Why does a circle have 360 degrees? →

Historical numeral systems

Babylonian (base 60): 𒌋𒌋𒌋𒁹𒁹 𒌋𒌋𒌋𒌋𒌋𒁹𒁹𒁹𒁹𒁹𒁹𒁹𒁹𒁹
Egyptian hieroglyphic: 𓆼𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓏺𓏺𓏺𓏺𓏺𓏺𓏺𓏺𓏺
Greek (Milesian): ͵αϡοθʹ
Mayan (base 20): 𝋤·𝋲·𝋳
Chinese: 一千九百七十九
Chinese (financial): 壹仟玖佰柒拾玖

In other modern scripts

Eastern Arabic ١٩٧٩ Devanagari १९७९ Bengali ১৯৭৯ Tamil ௧௯௭௯ Thai ๑๙๗๙ Tibetan ༡༩༧༩ Khmer ១៩៧៩ Lao ໑໙໗໙ Burmese ၁၉၇၉

Digit at this position in famous constants

π — Pi (π): Digit 1,979 = 6
e — Euler's number (e): Digit 1,979 = 4
φ — Golden ratio (φ): Digit 1,979 = 3
√2 — Pythagoras's (√2): Digit 1,979 = 1
ln 2 — Natural log of 2: Digit 1,979 = 9
γ — Euler-Mascheroni (γ): Digit 1,979 = 9

Also seen as

Prime neighborhood

Adjacent primes:

Previous prime: 1,973 (gap of 6)
Next prime: 1,987 (gap of 8)

Pair status: sexy with 1973.

Hex color

#0007BB

RGB(0, 7, 187)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.7.187.

Address: 0.0.7.187
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.7.187

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

Musical pitch

Heard as a frequency, 1,979 Hz is closest to:

Concert pitch (A4 = 440 Hz): B6 (1975.5 Hz, +3¢)
Scientific pitch (C4 = 256 Hz): B6 (1933.1 Hz, +41¢)
Baroque pitch (A4 = 415 Hz): C7 (1974.1 Hz, +4¢)

Position in π

The digit sequence 1979 first appears in π at position 2,905 of the decimal expansion (the 2,905ordinal-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 1979 on Pi Search ↗