Number

1,240

1,240 is a composite number, even, a calendar year.

Abundant Number Arithmetic Number Gapful Number Odious Number Pernicious Number Practical Number Recamán's Sequence Semiperfect Number Square Pyramidal Year

Historical context — 1240 AD

Calendar year

Year 1240 (MCCXL) was a leap year starting on Sunday of the Julian calendar.

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

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: Sunday
January 1, 1240
Ended on: Monday
December 31, 1240
Friday the 13ths: 3
3 Friday the 13ths this year.
Decade: 1240s
1240–1249
Century: 13th century
1201–1300
Millennium: 2nd millennium
1001–2000
Years ago: 786
786 years before 2026.

In other calendars

Hebrew: 5000 / 5001 AM
Rosh Hashanah falls in September/October.
Islamic Hijri: 637 / 638 AH
Lunar calendar; year spans differ from Gregorian.
Chinese: Year of the zodiac:Metal zodiac:Rat
Sexagenary cycle position 37 of 60. Lunar new year falls in late January / mid-February.
Buddhist Era: 1783 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
Persian Solar Hijri: 618 / 619 SH
Iranian calendar; Nowruz (new year) falls on the spring equinox.
Ethiopian: 1232 / 1233 ET
Year boundary at Enkutatash (September 11/12).
Indian National (Saka): 1162 / 1161 Saka
Indian national calendar; year starts in March.

Properties

Parity: Even
Digit count: 4
Digit sum: 7
Digit product: 0
Digital root: 7
Palindrome: No
Bit width: 11 bits
Reversed: 421
Recamán's sequence: a(8,508) = 1,240
Square (n²): 1,537,600
Cube (n³): 1,906,624,000
Divisor count: 16
σ(n) — sum of divisors: 2,880
φ(n) — Euler's totient: 480
Sum of prime factors: 42

Primality

Prime factorization: 2 ³ × 5 × 31

Nearest primes: 1,237 (−3) · 1,249 (+9)

Divisors & multiples

All divisors (16)

1 · 2 · 4 · 5 · 8 · 10 · 20 · 31 · 40 · 62 · 124 · 155 · 248 · 310 · 620 (half) · 1240

Aliquot sum (sum of proper divisors): 1,640

Factor pairs (a × b = 1,240)

1 × 1240

2 × 620

4 × 310

5 × 248

8 × 155

10 × 124

20 × 62

31 × 40

First multiples

1,240 · 2,480 (double) · 3,720 · 4,960 · 6,200 · 7,440 · 8,680 · 9,920 · 11,160 · 12,400

Sums & aliquot sequence

As consecutive integers: 246 + 247 + 248 + 249 + 250 70 + 71 + … + 85 25 + 26 + … + 55

Aliquot sequence: 1,240 → 1,640 → 2,140 → 2,396 → 1,804 → 1,724 → 1,300 → 1,738 → 1,142 → 574 → 434 → 334 → 170 → 154 → 134 → 70 → 74 — unresolved within range

Representations

In words: one thousand two hundred forty
Ordinal: 1240th
Roman numeral: MCCXL
Binary: 10011011000
Octal: 2330
Hexadecimal: 0x4D8
Base64: BNg=
One's complement: 64,295 (16-bit)

In other bases

ternary (3) 1200221

quaternary (4) 103120

quinary (5) 14430

senary (6) 5424

septenary (7) 3421

nonary (9) 1627

undecimal (11) a28

duodecimal (12) 874

tridecimal (13) 745

tetradecimal (14) 648

pentadecimal (15) 57a

Historical numeral systems

Babylonian (base 60): 𒌋𒌋 𒌋𒌋𒌋𒌋
Egyptian hieroglyphic: 𓆼𓍢𓍢𓎆𓎆𓎆𓎆
Greek (Milesian): ͵ασμʹ
Mayan (base 20): 𝋣·𝋢·𝋠
Chinese: 一千二百四十
Chinese (financial): 壹仟貳佰肆拾

In other modern scripts

Eastern Arabic ١٢٤٠ Devanagari १२४० Bengali ১২৪০ Tamil ௧௨௪௦ Thai ๑๒๔๐ Tibetan ༡༢༤༠ Khmer ១២៤០ Lao ໑໒໔໐ Burmese ၁၂၄၀

Digit at this position in famous constants

π — Pi (π): Digit 1,240 = 8
e — Euler's number (e): Digit 1,240 = 6
φ — Golden ratio (φ): Digit 1,240 = 7
√2 — Pythagoras's (√2): Digit 1,240 = 8
ln 2 — Natural log of 2: Digit 1,240 = 5
γ — Euler-Mascheroni (γ): Digit 1,240 = 6

Also seen as

Goldbach decomposition

Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 1240, here are decompositions:

3 + 1237 = 1240
11 + 1229 = 1240
17 + 1223 = 1240
23 + 1217 = 1240
47 + 1193 = 1240
53 + 1187 = 1240
59 + 1181 = 1240
89 + 1151 = 1240

Showing the first eight; more decompositions exist.

Unicode codepoint

Cyrillic Capital Letter Schwa

U+04D8

Uppercase letter (Lu)

UTF-8 encoding: D3 98 (2 bytes).

Lookup U+04D8 on Compart ↗ Lookup on FileFormat.Info ↗

Hex color

#0004D8

RGB(0, 4, 216)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.4.216.

Address: 0.0.4.216
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.4.216

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

Position in π

The digit sequence 1240 first appears in π at position 22,031 of the decimal expansion (the 22,031ordinal-suffix:st 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 1240 on Pi Search ↗