Number

1,601

1,601 is a prime, odd, a calendar year.

Arithmetic Number Chen Prime Cousin Prime Deficient Number Emirp Evil Number Flippable Prime Pythagorean Prime Recamán's Sequence Sexy Prime Sophie Germain Prime Squarefree Year

Notable events — 1601 AD

Feb 25 The Earl of Essex is executed for treason after an attempted coup against Elizabeth I.
Oct 24 Astronomer Tycho Brahe dies in Prague.
Sep 23 An Irish-Spanish force is defeated at Kinsale.

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, 1601
Ended on: Monday
December 31, 1601
Friday the 13ths: 2
2 Friday the 13ths this year.
Easter Sunday: April 22
Sunday, April 22, 1601
Decade: 1600s
1600–1609
Century: 17th century
1601–1700
Millennium: 2nd millennium
1001–2000
Years ago: 425
425 years before 2026.

In other calendars

Hebrew: 5361 / 5362 AM
Rosh Hashanah falls in September/October.
Islamic Hijri: 1009 / 1010 AH
Lunar calendar; year spans differ from Gregorian.
Chinese: Year of the zodiac:Metal zodiac:Ox
Sexagenary cycle position 38 of 60. Lunar new year falls in late January / mid-February.
Buddhist Era: 2144 BE
Counted from the parinirvana of the Buddha (Theravada / Thai / Sri Lankan convention).
Persian Solar Hijri: 979 / 980 SH
Iranian calendar; Nowruz (new year) falls on the spring equinox.
Ethiopian: 1593 / 1594 ET
Year boundary at Enkutatash (September 11/12).
Indian National (Saka): 1523 / 1522 Saka
Indian national calendar; year starts in March.

Properties

Parity: Odd
Digit count: 4
Digit sum: 8
Digit product: 0
Digital root: 8
Palindrome: No
Bit width: 11 bits
Reversed: 1,061
Flips to (rotate 180°): 1,091
Recamán's sequence: a(1,342) = 1,601
Square (n²): 2,563,201
Cube (n³): 4,103,684,801
Divisor count: 2
σ(n) — sum of divisors: 1,602
φ(n) — Euler's totient: 1,600

Primality

1,601 is prime. It has exactly two divisors: 1 and itself.

Divisors & multiples

All divisors (2)

1 · 1601

Aliquot sum (sum of proper divisors): 1

Factor pairs (a × b = 1,601)

1 × 1601

First multiples

1,601 · 3,202 (double) · 4,803 · 6,404 · 8,005 · 9,606 · 11,207 · 12,808 · 14,409 · 16,010

Sums & aliquot sequence

As a sum of two squares: 1² + 40²

As consecutive integers: 800 + 801

Representations

In words: one thousand six hundred one
Ordinal: 1601st
Roman numeral: MDCI
Binary: 11001000001
Octal: 3101
Hexadecimal: 0x641
Base64: BkE=
One's complement: 63,934 (16-bit)

In other bases

ternary (3) 2012022

quaternary (4) 121001

quinary (5) 22401

senary (6) 11225

septenary (7) 4445

nonary (9) 2168

undecimal (11) 1226

duodecimal (12) b15

tridecimal (13) 962

tetradecimal (14) 825

pentadecimal (15) 71b

Historical numeral systems

Babylonian (base 60): 𒌋𒌋𒁹𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒌋𒌋𒁹
Egyptian hieroglyphic: 𓆼𓍢𓍢𓍢𓍢𓍢𓍢𓏺
Greek (Milesian): ͵αχαʹ
Mayan (base 20): 𝋤·𝋠·𝋡
Chinese: 一千六百零一
Chinese (financial): 壹仟陸佰零壹

In other modern scripts

Eastern Arabic ١٦٠١ Devanagari १६०१ Bengali ১৬০১ Tamil ௧௬௦௧ Thai ๑๖๐๑ Tibetan ༡༦༠༡ Khmer ១៦០១ Lao ໑໖໐໑ Burmese ၁၆၀၁

Digit at this position in famous constants

π — Pi (π): Digit 1,601 = 0
e — Euler's number (e): Digit 1,601 = 9
φ — Golden ratio (φ): Digit 1,601 = 4
√2 — Pythagoras's (√2): Digit 1,601 = 8
ln 2 — Natural log of 2: Digit 1,601 = 4
γ — Euler-Mascheroni (γ): Digit 1,601 = 3

Also seen as

Prime neighborhood

Adjacent primes:

Previous prime: 1,597 (gap of 4)
Next prime: 1,607 (gap of 6)

Pair status: cousin with 1597, sexy with 1607.

Unicode codepoint

Arabic Letter Feh

U+0641

Other letter (Lo)

UTF-8 encoding: D9 81 (2 bytes).

Lookup U+0641 on Compart ↗ Lookup on FileFormat.Info ↗

Hex color

#000641

RGB(0, 6, 65)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.6.65.

Address: 0.0.6.65
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.6.65

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

Possible US bank routing number

This passes the ABA routing number checksum and matches the Federal Reserve numbering scheme.

Routing number

000001601

Federal Reserve

United States Government

Banks operate many routing numbers per state and division; an unmatched checksum-valid number can still be a real RTN at a smaller institution.

Look up on FedACH (official) ↗ Search Google for routing number 000001601 ↗

Position in π

The digit sequence 1601 first appears in π at position 7,268 of the decimal expansion (the 7,268ordinal-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 1601 on Pi Search ↗