Live analysis

21,200

21,200 is a composite number, even.

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.).

21,200 (twenty-one thousand two hundred) is an even 5-digit number. It is a composite number with 30 divisors, and factors as 2⁴ × 5² × 53. Its proper divisors sum to 30,694, more than the number itself, making it an abundant number. Written other ways, in hexadecimal, 0x52D0.

Abundant Number Evil Number Gapful Number Harshad / Niven Practical Number Recamán's Sequence Self-Describing Number Semiperfect Number

Interestingness

★ ★ ★ ★ ☆

6 notable facts · grade B

21,188 21,189 21,190 21,191 21,192 21,193 21,194 21,195 21,196 21,197 21,198 21,199 21,200 21,201 21,202 21,203 21,204 21,205 21,206 21,207 21,208 21,209 21,210 21,211 21,212

less more

Properties

Parity: Even
Digit count: 5
Digit sum: 5
Digit product: 0
Digital root: 5
Palindrome: No
Bit width: 15 bits
Reversed: 212
Recamán's sequence: a(41,439) = 21,200
Square (n²): 449,440,000
Cube (n³): 9,528,128,000,000
Divisor count: 30
σ(n) — sum of divisors: 51,894
φ(n) — Euler's totient: 8,320
Sum of prime factors: 71

Primality

Prime factorization: 2 ⁴ × 5 ² × 53

Nearest primes: 21,193 (−7) · 21,211 (+11)

Divisors & multiples

All divisors (30)

1 · 2 · 4 · 5 · 8 · 10 · 16 · 20 · 25 · 40 · 50 · 53 · 80 · 100 · 106 · 200 · 212 · 265 · 400 · 424 · 530 · 848 · 1060 · 1325 · 2120 · 2650 · 4240 · 5300 · 10600 (half) · 21200

Aliquot sum (sum of proper divisors): 30,694

Factor pairs (a × b = 21,200)

1 × 21200

2 × 10600

4 × 5300

5 × 4240

8 × 2650

10 × 2120

16 × 1325

20 × 1060

25 × 848

40 × 530

50 × 424

53 × 400

80 × 265

100 × 212

106 × 200

First multiples

21,200 · 42,400 (double) · 63,600 · 84,800 · 106,000 · 127,200 · 148,400 · 169,600 · 190,800 · 212,000

Sums & aliquot sequence

As a sum of two squares: 40² + 140² = 52² + 136² = 88² + 116²

As consecutive integers: 4,238 + 4,239 + 4,240 + 4,241 + 4,242 836 + 837 + … + 860 647 + 648 + … + 678 374 + 375 + … + 426

Aliquot sequence: 21,200 → 30,694 → 16,106 → 8,056 → 8,144 → 7,666 → 3,836 → 3,892 → 3,948 → 6,804 → 13,580 → 19,348 → 19,404 → 42,840 → 125,640 → 283,860 → 633,420 — unresolved within range

Continued fraction of √n

√21,200 = [145; (1, 1, 1, 1, 17, 1, 1, 1, 1, 290)]

Period length 10 — the block in parentheses repeats forever.

Representations

In words: twenty-one thousand two hundred
Ordinal: 21200th
Binary: 101001011010000
Octal: 51320
Hexadecimal: 0x52D0
Base64: UtA=
One's complement: 44,335 (16-bit)
Scientific notation: 2.12 × 10⁴
As a duration: 21,200 s = 5 hours, 53 minutes, 20 seconds

In other bases

ternary (3) 1002002012

quaternary (4) 11023100

quinary (5) 1134300

senary (6) 242052

septenary (7) 115544

nonary (9) 32065

undecimal (11) 14a23

duodecimal (12) 10328

tridecimal (13) 985a

tetradecimal (14) 7a24

pentadecimal (15) 6435

As an angle

21,200° = 58 × 360° + 320°

320° ≈ 5.585 rad

Compass bearing: NW (northwest)

Why does a circle have 360 degrees? →

Historical numeral systems

Babylonian (base 60): 𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒌋𒌋𒌋𒁹𒁹𒁹 𒌋𒌋
Egyptian hieroglyphic: 𓂍𓂍𓆼𓍢𓍢
Greek (Milesian): ͵κασʹ
Mayan (base 20): 𝋢·𝋭·𝋠·𝋠
Chinese: 二萬一千二百
Chinese (financial): 貳萬壹仟貳佰

In other modern scripts

Eastern Arabic ٢١٢٠٠ Devanagari २१२०० Bengali ২১২০০ Tamil ௨௧௨௦௦ Thai ๒๑๒๐๐ Tibetan ༢༡༢༠༠ Khmer ២១២០០ Lao ໒໑໒໐໐ Burmese ၂၁၂၀၀

Digit at this position in famous constants

π — Pi (π): Digit 21,200 = 6
e — Euler's number (e): Digit 21,200 = 5
φ — Golden ratio (φ): Digit 21,200 = 3
√2 — Pythagoras's (√2): Digit 21,200 = 7
ln 2 — Natural log of 2: Digit 21,200 = 1
γ — Euler-Mascheroni (γ): Digit 21,200 = 8

Also seen as

Goldbach decomposition

Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 21200, here are decompositions:

7 + 21193 = 21200
13 + 21187 = 21200
31 + 21169 = 21200
37 + 21163 = 21200
43 + 21157 = 21200
61 + 21139 = 21200
79 + 21121 = 21200
139 + 21061 = 21200

Showing the first eight; more decompositions exist.

Unicode codepoint

勐

CJK Unified Ideograph-52D0

U+52D0

Other letter (Lo)

UTF-8 encoding: E5 8B 90 (3 bytes).

Lookup U+52D0 on Compart ↗ Lookup on FileFormat.Info ↗

Hex color

#0052D0

RGB(0, 82, 208)

IPv4 address

As an unsigned 32-bit integer, this is the IPv4 address 0.0.82.208.

Address: 0.0.82.208
Class: reserved
IPv4-mapped IPv6: ::ffff:0.0.82.208

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

Position in π

The digit sequence 21200 first appears in π at position 361,276 of the decimal expansion (the 361,276ordinal-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 21200 on Pi Search ↗