Number

3,691

3,691 is a prime, odd.

3,691 (three thousand six hundred ninety-one) is an odd 4-digit number. It is a prime number — divisible only by 1 and itself. Written other ways, in Roman numerals it is MMMDCXCI and in binary, 111001101011.

Arithmetic Number Chen Prime Cube-Free Deficient Number Evil Number Prime Recamán's Sequence Sexy Prime Squarefree

Interestingness

★ ★ ★ ★ ☆

7 notable facts · grade B

3,679 3,680 3,681 3,682 3,683 3,684 3,685 3,686 3,687 3,688 3,689 3,690 3,691 3,692 3,693 3,694 3,695 3,696 3,697 3,698 3,699 3,700 3,701 3,702 3,703

less more

Properties

Parity: Odd
Digit count: 4
Digit sum: 19
Digit product: 162
Digital root: 1
Palindrome: No
Bit width: 12 bits
Reversed: 1,963
Recamán's sequence: a(1,010) = 3,691
Square (n²): 13,623,481
Cube (n³): 50,284,268,371
Divisor count: 2
σ(n) — sum of divisors: 3,692
φ(n) — Euler's totient: 3,690

Primality

3,691 is prime. It has exactly two divisors: 1 and itself.

Divisors & multiples

All divisors (2)

1 · 3691

Aliquot sum (sum of proper divisors): 1

Factor pairs (a × b = 3,691)

1 × 3691

First multiples

3,691 · 7,382 (double) · 11,073 · 14,764 · 18,455 · 22,146 · 25,837 · 29,528 · 33,219 · 36,910

Sums & aliquot sequence

As consecutive integers: 1,845 + 1,846

Continued fraction of √n

√3,691 = [60; (1, 3, 17, 9, 3, 2, 6, 3, 7, 1, 3, 1, 1, 1, 1, 1, 2, 1, 5, 1, 2, 23, 1, 19, …)]

Representations

In words: three thousand six hundred ninety-one
Ordinal: 3691st
Roman numeral: MMMDCXCI
Binary: 111001101011
Octal: 7153
Hexadecimal: 0xE6B
Base64: Dms=
One's complement: 61,844 (16-bit)
Scientific notation: 3.691 × 10³
As a duration: 3,691 s = 1 hour, 1 minute, 31 seconds

In other bases

ternary (3) 12001201

quaternary (4) 321223

quinary (5) 104231

senary (6) 25031

septenary (7) 13522

nonary (9) 5051

undecimal (11) 2856

duodecimal (12) 2177

tridecimal (13) 18ac

tetradecimal (14) 14b9

pentadecimal (15) 1161

As an angle

3,691° = 10 × 360° + 91°

91° ≈ 1.588 rad

Compass bearing: E (east)

Why does a circle have 360 degrees? →

Historical numeral systems

Babylonian (base 60): 𒁹 𒁹 𒌋𒌋𒌋𒁹
Egyptian hieroglyphic: 𓆼𓆼𓆼𓍢𓍢𓍢𓍢𓍢𓍢𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓏺
Greek (Milesian): ͵γχϟαʹ
Mayan (base 20): 𝋩·𝋤·𝋫
Chinese: 三千六百九十一
Chinese (financial): 參仟陸佰玖拾壹

In other modern scripts

Eastern Arabic ٣٦٩١ Devanagari ३६९१ Bengali ৩৬৯১ Tamil ௩௬௯௧ Thai ๓๖๙๑ Tibetan ༣༦༩༡ Khmer ៣៦៩១ Lao ໓໖໙໑ Burmese ၃၆၉၁

Digit at this position in famous constants

π — Pi (π): Digit 3,691 = 1
e — Euler's number (e): Digit 3,691 = 6
φ — Golden ratio (φ): Digit 3,691 = 4
√2 — Pythagoras's (√2): Digit 3,691 = 8
ln 2 — Natural log of 2: Digit 3,691 = 9
γ — Euler-Mascheroni (γ): Digit 3,691 = 6

Also seen as

Prime neighborhood

Adjacent primes:

Previous prime: 3,677 (gap of 14)
Next prime: 3,697 (gap of 6)

Pair status: sexy with 3697.

Hex color

#000E6B

RGB(0, 14, 107)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.14.107.

Address: 0.0.14.107
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.14.107

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

Musical pitch

Heard as a frequency, 3,691 Hz is closest to:

Concert pitch (A4 = 440 Hz): A♯7 (3729.3 Hz, -18¢)
Scientific pitch (C4 = 256 Hz): A♯7 (3649.1 Hz, +20¢)
Baroque pitch (A4 = 415 Hz): B7 (3726.6 Hz, -17¢)

Position in π

The digit sequence 3691 first appears in π at position 16,236 of the decimal expansion (the 16,236ordinal-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 3691 on Pi Search ↗