Live analysis

4,991

4,991 is a composite number, odd.

This number doesn't have a permanent NumberWiki page yet — what you see below is computed live. Pages get added to the permanent index when they're notable (years, primes, curated, etc.).

4,991 (four thousand nine hundred ninety-one) is an odd 4-digit number. It is a composite number with 8 divisors, and factors as 7 × 23 × 31. Written other ways, in hexadecimal, 0x137F.

Arithmetic Number Cube-Free Deficient Number Evil Number Harshad / Niven Recamán's Sequence Sphenic Number Squarefree

Interestingness

★ ★ ★ ★ ☆

6 notable facts · grade B

4,979 4,980 4,981 4,982 4,983 4,984 4,985 4,986 4,987 4,988 4,989 4,990 4,991 4,992 4,993 4,994 4,995 4,996 4,997 4,998 4,999 5,000 5,001 5,002 5,003

less more

Properties

Parity: Odd
Digit count: 4
Digit sum: 23
Digit product: 324
Digital root: 5
Palindrome: No
Bit width: 13 bits
Reversed: 1,994
Recamán's sequence: a(28,146) = 4,991
Square (n²): 24,910,081
Cube (n³): 124,326,214,271
Divisor count: 8
σ(n) — sum of divisors: 6,144
φ(n) — Euler's totient: 3,960
Sum of prime factors: 61

Primality

Prime factorization: 7 × 23 × 31

Nearest primes: 4,987 (−4) · 4,993 (+2)

Divisors & multiples

All divisors (8)

1 · 7 · 23 · 31 · 161 · 217 · 713 · 4991

Aliquot sum (sum of proper divisors): 1,153

Factor pairs (a × b = 4,991)

1 × 4991

7 × 713

23 × 217

31 × 161

First multiples

4,991 · 9,982 (double) · 14,973 · 19,964 · 24,955 · 29,946 · 34,937 · 39,928 · 44,919 · 49,910

Sums & aliquot sequence

As consecutive integers: 2,495 + 2,496 710 + 711 + … + 716 350 + 351 + … + 363 206 + 207 + … + 228

Aliquot sequence: 4,991 → 1,153 → 1 → 0 — terminates at zero

Continued fraction of √n

√4,991 = [70; (1, 1, 1, 4, 1, 69, 1, 4, 1, 1, 1, 140)]

Period length 12 — the block in parentheses repeats forever.

Representations

In words: four thousand nine hundred ninety-one
Ordinal: 4991st
Binary: 1001101111111
Octal: 11577
Hexadecimal: 0x137F
Base64: E38=
One's complement: 60,544 (16-bit)
Scientific notation: 4.991 × 10³
As a duration: 4,991 s = 1 hour, 23 minutes, 11 seconds

In other bases

ternary (3) 20211212

quaternary (4) 1031333

quinary (5) 124431

senary (6) 35035

septenary (7) 20360

nonary (9) 6755

undecimal (11) 3828

duodecimal (12) 2a7b

tridecimal (13) 236c

tetradecimal (14) 1b67

pentadecimal (15) 172b

As an angle

4,991° = 13 × 360° + 311°

311° ≈ 5.428 rad

Compass bearing: NW (northwest)

Why does a circle have 360 degrees? →

Historical numeral systems

Babylonian (base 60): 𒁹 𒌋𒌋𒁹𒁹𒁹 𒌋𒁹
Egyptian hieroglyphic: 𓆼𓆼𓆼𓆼𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓍢𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓎆𓏺
Greek (Milesian): ͵δϡϟαʹ
Mayan (base 20): 𝋬·𝋩·𝋫
Chinese: 四千九百九十一
Chinese (financial): 肆仟玖佰玖拾壹

In other modern scripts

Eastern Arabic ٤٩٩١ Devanagari ४९९१ Bengali ৪৯৯১ Tamil ௪௯௯௧ Thai ๔๙๙๑ Tibetan ༤༩༩༡ Khmer ៤៩៩១ Lao ໔໙໙໑ Burmese ၄၉၉၁

Digit at this position in famous constants

π — Pi (π): Digit 4,991 = 7
e — Euler's number (e): Digit 4,991 = 7
φ — Golden ratio (φ): Digit 4,991 = 1
√2 — Pythagoras's (√2): Digit 4,991 = 1
ln 2 — Natural log of 2: Digit 4,991 = 3
γ — Euler-Mascheroni (γ): Digit 4,991 = 8

Also seen as

Hex color

#00137F

RGB(0, 19, 127)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.19.127.

Address: 0.0.19.127
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.19.127

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

Musical pitch

Heard as a frequency, 4,991 Hz is closest to:

Concert pitch (A4 = 440 Hz): D♯8 (4978 Hz, +5¢)
Scientific pitch (C4 = 256 Hz): D♯8 (4871 Hz, +42¢)
Baroque pitch (A4 = 415 Hz): E8 (4974.4 Hz, +6¢)

Position in π

The digit sequence 4991 first appears in π at position 1,531 of the decimal expansion (the 1,531ordinal-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 4991 on Pi Search ↗