Number

1,290

1,290 is a composite number, even, a calendar year.

1,290 (one thousand two hundred ninety) is an even 4-digit number. It is a composite number with 16 divisors, and factors as 2 × 3 × 5 × 43. Its proper divisors sum to 1,878, more than the number itself, making it an abundant number. Written other ways, in Roman numerals it is MCCXC and in binary, 10100001010.

Abundant Number Arithmetic Number Cube-Free Evil Number Gapful Number Happy Number Practical Number Recamán's Sequence Semiperfect Number Squarefree Year

Interestingness

★ ★ ★ ★ ★

8 notable facts · grade A

1,278 1,279 1,280 1,281 1,282 1,283 1,284 1,285 1,286 1,287 1,288 1,289 1,290 1,291 1,292 1,293 1,294 1,295 1,296 1,297 1,298 1,299 1,300 1,301 1,302

less more

Historical context — 1290 AD

Calendar year

Year 1290 (MCCXC) was a common year starting on Sunday of the Julian calendar.

Excerpt from Wikipedia (en) ↗ · Licensed CC BY-SA 4.0 Read the full article on Wikipedia →

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: Sunday
January 1, 1290
Ended on: Sunday
December 31, 1290
Friday the 13ths: 2
2 Friday the 13ths this year.
Decade: 1290s
1290–1299
Century: 13th century
1201–1300
Millennium: 2nd millennium
1001–2000
Years ago: 736
736 years before 2026.

In other calendars

Hebrew: 5050 / 5051 AM
Rosh Hashanah falls in September/October.
Islamic Hijri: 688 / 689 AH
Lunar calendar; year spans differ from Gregorian.
Chinese: Year of the zodiac:Metal zodiac:Tiger
Sexagenary cycle position 27 of 60. Lunar new year falls in late January / mid-February.
Buddhist Era: 1833 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
Persian Solar Hijri: 668 / 669 SH
Iranian calendar; Nowruz (new year) falls on the spring equinox.
Ethiopian: 1282 / 1283 ET
Year boundary at Enkutatash (September 11/12).
Indian National (Saka): 1212 / 1211 Saka
Indian national calendar; year starts in March.

Properties

Parity: Even
Digit count: 4
Digit sum: 12
Digit product: 0
Digital root: 3
Palindrome: No
Bit width: 11 bits
Reversed: 921
Recamán's sequence: a(30,468) = 1,290
Square (n²): 1,664,100
Cube (n³): 2,146,689,000
Divisor count: 16
σ(n) — sum of divisors: 3,168
φ(n) — Euler's totient: 336
Sum of prime factors: 53

Primality

Prime factorization: 2 × 3 × 5 × 43

Nearest primes: 1,289 (−1) · 1,291 (+1)

Divisors & multiples

All divisors (16)

1 · 2 · 3 · 5 · 6 · 10 · 15 · 30 · 43 · 86 · 129 · 215 · 258 · 430 · 645 (half) · 1290

Aliquot sum (sum of proper divisors): 1,878

Factor pairs (a × b = 1,290)

1 × 1290

2 × 645

3 × 430

5 × 258

6 × 215

10 × 129

15 × 86

30 × 43

First multiples

1,290 · 2,580 (double) · 3,870 · 5,160 · 6,450 · 7,740 · 9,030 · 10,320 · 11,610 · 12,900

Sums & aliquot sequence

As consecutive integers: 429 + 430 + 431 321 + 322 + 323 + 324 256 + 257 + 258 + 259 + 260 102 + 103 + … + 113

Aliquot sequence: 1,290 → 1,878 → 1,890 → 3,870 → 6,426 → 10,854 → 13,830 → 19,434 → 20,886 → 21,606 → 25,098 → 26,742 → 26,754 → 40,446 → 63,234 → 77,406 → 110,754 — unresolved within range

Continued fraction of √n

√1,290 = [35; (1, 10, 1, 70)]

Period length 4 — the block in parentheses repeats forever.

Representations

In words: one thousand two hundred ninety
Ordinal: 1290th
Roman numeral: MCCXC
Binary: 10100001010
Octal: 2412
Hexadecimal: 0x50A
Base64: BQo=
One's complement: 64,245 (16-bit)
Scientific notation: 1.29 × 10³
As a duration: 1,290 s = 21 minutes, 30 seconds

In other bases

ternary (3) 1202210

quaternary (4) 110022

quinary (5) 20130

senary (6) 5550

septenary (7) 3522

nonary (9) 1683

undecimal (11) a73

duodecimal (12) 8b6

tridecimal (13) 783

tetradecimal (14) 682

pentadecimal (15) 5b0

As an angle

1,290° = 3 × 360° + 210°

210° ≈ 3.665 rad

Compass bearing: SSW (south-southwest)

Why does a circle have 360 degrees? →

Historical numeral systems

Babylonian (base 60): 𒌋𒌋𒁹 𒌋𒌋𒌋
Egyptian hieroglyphic: 𓆼𓍢𓍢𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓎆
Greek (Milesian): ͵ασϟʹ
Mayan (base 20): 𝋣·𝋤·𝋪
Chinese: 一千二百九十
Chinese (financial): 壹仟貳佰玖拾

In other modern scripts

Eastern Arabic ١٢٩٠ Devanagari १२९० Bengali ১২৯০ Tamil ௧௨௯௦ Thai ๑๒๙๐ Tibetan ༡༢༩༠ Khmer ១២៩០ Lao ໑໒໙໐ Burmese ၁၂၉၀

Digit at this position in famous constants

π — Pi (π): Digit 1,290 = 8
e — Euler's number (e): Digit 1,290 = 4
φ — Golden ratio (φ): Digit 1,290 = 2
√2 — Pythagoras's (√2): Digit 1,290 = 4
ln 2 — Natural log of 2: Digit 1,290 = 8
γ — Euler-Mascheroni (γ): Digit 1,290 = 2

Also seen as

Goldbach decomposition

Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 1290, here are decompositions:

7 + 1283 = 1290
11 + 1279 = 1290
13 + 1277 = 1290
31 + 1259 = 1290
41 + 1249 = 1290
53 + 1237 = 1290
59 + 1231 = 1290
61 + 1229 = 1290

Showing the first eight; more decompositions exist.

Unicode codepoint

Cyrillic Capital Letter Komi Nje

U+050A

Uppercase letter (Lu)

UTF-8 encoding: D4 8A (2 bytes).

Lookup U+050A on Compart ↗ Lookup on FileFormat.Info ↗

Hex color

#00050A

RGB(0, 5, 10)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.5.10.

Address: 0.0.5.10
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.5.10

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

Musical pitch

Heard as a frequency, 1,290 Hz is closest to:

Concert pitch (A4 = 440 Hz): E6 (1318.5 Hz, -38¢)
Scientific pitch (C4 = 256 Hz): E6 (1290.2 Hz, exact)
Baroque pitch (A4 = 415 Hz): F6 (1317.5 Hz, -37¢)

Position in π

The digit sequence 1290 first appears in π at position 712 of the decimal expansion (the 712ordinal-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 1290 on Pi Search ↗