Number

751

751 is a prime, odd, a calendar year.

751 (seven hundred fifty-one) is an odd 3-digit number. It is a prime number — divisible only by 1 and itself. Written other ways, in Roman numerals it is DCCLI and in binary, 1011101111.

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

Interestingness

★ ★ ★ ★ ★

9 notable facts · grade A

739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763

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Notable events — 751 AD

Undated The Abbasid Revolution overthrows the Umayyad Caliphate; Pepin the Short founds the Carolingian dynasty.

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

Historical context — 751 BC

Decade

This article concerns the period 759 BC – 750 BC.

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: Monday
January 1, 751
Ended on: Monday
December 31, 751
Friday the 13ths: 2
2 Friday the 13ths this year.
Decade: 750s
750–759
Century: 8th century
701–800
Millennium: 1st millennium
1–1000
Years ago: 1,275
1275 years before 2026.

In other calendars

Hebrew: 4511 / 4512 AM
Rosh Hashanah falls in September/October.
Islamic Hijri: 133 / 134 AH
Lunar calendar; year spans differ from Gregorian.
Chinese: Year of the zodiac:Metal zodiac:Rabbit
Sexagenary cycle position 28 of 60. Lunar new year falls in late January / mid-February.
Buddhist Era: 1294 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
Persian Solar Hijri: 129 / 130 SH
Iranian calendar; Nowruz (new year) falls on the spring equinox.
Ethiopian: 743 / 744 ET
Year boundary at Enkutatash (September 11/12).
Indian National (Saka): 673 / 672 Saka
Indian national calendar; year starts in March.

Properties

Parity: Odd
Digit count: 3
Digit sum: 13
Digit product: 35
Digital root: 4
Palindrome: No
Bit width: 10 bits
Reversed: 157
Recamán's sequence: a(929) = 751
Square (n²): 564,001
Cube (n³): 423,564,751
Divisor count: 2
σ(n) — sum of divisors: 752
φ(n) — Euler's totient: 750

Primality

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

Divisors & multiples

All divisors (2)

1 · 751

Aliquot sum (sum of proper divisors): 1

Factor pairs (a × b = 751)

1 × 751

First multiples

751 · 1,502 (double) · 2,253 · 3,004 · 3,755 · 4,506 · 5,257 · 6,008 · 6,759 · 7,510

Sums & aliquot sequence

As consecutive integers: 375 + 376

Continued fraction of √n

√751 = [27; (2, 2, 8, 1, 2, 1, 3, 5, 1, 4, 1, 1, 1, 3, 1, 1, 3, 10, 1, 2, 7, 2, 17, 1, …)]

Period length 52 — the block in parentheses repeats forever.

Representations

In words: seven hundred fifty-one
Ordinal: 751st
Roman numeral: DCCLI
Binary: 1011101111
Octal: 1357
Hexadecimal: 0x2EF
Base64: Au8=
One's complement: 64,784 (16-bit)
Scientific notation: 7.51 × 10²
As a duration: 751 s = 12 minutes, 31 seconds

In other bases

ternary (3) 1000211

quaternary (4) 23233

quinary (5) 11001

senary (6) 3251

septenary (7) 2122

nonary (9) 1024

undecimal (11) 623

duodecimal (12) 527

tridecimal (13) 45a

tetradecimal (14) 3b9

pentadecimal (15) 351

As an angle

751° = 2 × 360° + 31°

31° ≈ 0.541 rad

Compass bearing: NNE (north-northeast)

Why does a circle have 360 degrees? →

Historical numeral systems

Babylonian (base 60): 𒌋𒁹𒁹 𒌋𒌋𒌋𒁹
Egyptian hieroglyphic: 𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓎆𓎆𓎆𓎆𓎆𓏺
Greek (Milesian): ψναʹ
Mayan (base 20): 𝋡·𝋱·𝋫
Chinese: 七百五十一
Chinese (financial): 柒佰伍拾壹

In other modern scripts

Eastern Arabic ٧٥١ Devanagari ७५१ Bengali ৭৫১ Tamil ௭௫௧ Thai ๗๕๑ Tibetan ༧༥༡ Khmer ៧៥១ Lao ໗໕໑ Burmese ၇၅၁

Digit at this position in famous constants

π — Pi (π): Digit 751 = 0
e — Euler's number (e): Digit 751 = 2
φ — Golden ratio (φ): Digit 751 = 6
√2 — Pythagoras's (√2): Digit 751 = 4
ln 2 — Natural log of 2: Digit 751 = 1
γ — Euler-Mascheroni (γ): Digit 751 = 9

Also seen as

Prime neighborhood

Adjacent primes:

Previous prime: 743 (gap of 8)
Next prime: 757 (gap of 6)

Pair status: sexy with 757.

Unicode codepoint

Modifier Letter Low Down Arrowhead

U+02EF

Modifier symbol (Sk)

UTF-8 encoding: CB AF (2 bytes).

Lookup U+02EF on Compart ↗ Lookup on FileFormat.Info ↗

Hex color

#0002EF

RGB(0, 2, 239)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.2.239.

Address: 0.0.2.239
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.2.239

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

Musical pitch

Heard as a frequency, 751 Hz is closest to:

Concert pitch (A4 = 440 Hz): F♯5 (740 Hz, +26¢)
Scientific pitch (C4 = 256 Hz): G5 (767.1 Hz, -37¢)
Baroque pitch (A4 = 415 Hz): G5 (739.4 Hz, +27¢)