Number

1,651

1,651 is a composite number, odd, a calendar year.

Arithmetic Number Deficient Number Harshad / Niven Heptagonal Odious Number Pernicious Number Recamán's Sequence Semiprime Squarefree Year

Notable events — 1651 AD

Sep 3 Cromwell defeats Charles II at Worcester, ending the English Civil War.
Oct 9 Parliament passes the Navigation Act.
Undated Thomas Hobbes publishes Leviathan.

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: Sunday
January 1, 1651
Ended on: Sunday
December 31, 1651
Friday the 13ths: 2
2 Friday the 13ths this year.
Easter Sunday: April 9
Sunday, April 9, 1651
Decade: 1650s
1650–1659
Century: 17th century
1601–1700
Millennium: 2nd millennium
1001–2000
Years ago: 375
375 years before 2026.

In other calendars

Hebrew: 5411 / 5412 AM
Rosh Hashanah falls in September/October.
Islamic Hijri: 1061 / 1062 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: 2194 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
Persian Solar Hijri: 1029 / 1030 SH
Iranian calendar; Nowruz (new year) falls on the spring equinox.
Ethiopian: 1643 / 1644 ET
Year boundary at Enkutatash (September 11/12).
Indian National (Saka): 1573 / 1572 Saka
Indian national calendar; year starts in March.

Properties

Parity: Odd
Digit count: 4
Digit sum: 13
Digit product: 30
Digital root: 4
Palindrome: No
Bit width: 11 bits
Reversed: 1,561
Recamán's sequence: a(870) = 1,651
Square (n²): 2,725,801
Cube (n³): 4,500,297,451
Divisor count: 4
σ(n) — sum of divisors: 1,792
φ(n) — Euler's totient: 1,512
Sum of prime factors: 140

Primality

Prime factorization: 13 × 127

Nearest primes: 1,637 (−14) · 1,657 (+6)

Divisors & multiples

All divisors (4)

1 · 13 · 127 · 1651

Aliquot sum (sum of proper divisors): 141

Factor pairs (a × b = 1,651)

1 × 1651

13 × 127

First multiples

1,651 · 3,302 (double) · 4,953 · 6,604 · 8,255 · 9,906 · 11,557 · 13,208 · 14,859 · 16,510

Sums & aliquot sequence

As consecutive integers: 825 + 826 121 + 122 + … + 133 51 + 52 + … + 76

Aliquot sequence: 1,651 → 141 → 51 → 21 → 11 → 1 → 0 — terminates at zero

Representations

In words: one thousand six hundred fifty-one
Ordinal: 1651st
Roman numeral: MDCLI
Binary: 11001110011
Octal: 3163
Hexadecimal: 0x673
Base64: BnM=
One's complement: 63,884 (16-bit)

In other bases

ternary (3) 2021011

quaternary (4) 121303

quinary (5) 23101

senary (6) 11351

septenary (7) 4546

nonary (9) 2234

undecimal (11) 1271

duodecimal (12) b57

tridecimal (13) 9a0

tetradecimal (14) 85d

pentadecimal (15) 751

Historical numeral systems

Babylonian (base 60): 𒌋𒌋𒁹𒁹𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒌋𒁹
Egyptian hieroglyphic: 𓆼𓍢𓍢𓍢𓍢𓍢𓍢𓎆𓎆𓎆𓎆𓎆𓏺
Greek (Milesian): ͵αχναʹ
Mayan (base 20): 𝋤·𝋢·𝋫
Chinese: 一千六百五十一
Chinese (financial): 壹仟陸佰伍拾壹

In other modern scripts

Eastern Arabic ١٦٥١ Devanagari १६५१ Bengali ১৬৫১ Tamil ௧௬௫௧ Thai ๑๖๕๑ Tibetan ༡༦༥༡ Khmer ១៦៥១ Lao ໑໖໕໑ Burmese ၁၆၅၁

Digit at this position in famous constants

π — Pi (π): Digit 1,651 = 8
e — Euler's number (e): Digit 1,651 = 7
φ — Golden ratio (φ): Digit 1,651 = 1
√2 — Pythagoras's (√2): Digit 1,651 = 9
ln 2 — Natural log of 2: Digit 1,651 = 5
γ — Euler-Mascheroni (γ): Digit 1,651 = 9

Also seen as

Unicode codepoint

Arabic Letter Alef With Wavy Hamza Below

U+0673

Other letter (Lo)

UTF-8 encoding: D9 B3 (2 bytes).

Lookup U+0673 on Compart ↗ Lookup on FileFormat.Info ↗

Hex color

#000673

RGB(0, 6, 115)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.6.115.

Address: 0.0.6.115
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.6.115

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

Position in π

The digit sequence 1651 first appears in π at position 3,529 of the decimal expansion (the 3,529ordinal-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 1651 on Pi Search ↗