21,002
21,002 is a composite number, even.
Properties
- Parity
- Even
- Digit count
- 5
- Digit sum
- 5
- Digit product
- 0
- Digital root
- 5
- Palindrome
- No
- Bit width
- 15 bits
- Reversed
- 20,012
- Recamán's sequence
- a(41,835) = 21,002
- Square (n²)
- 441,084,004
- Cube (n³)
- 9,263,646,252,008
- Divisor count
- 4
- σ(n) — sum of divisors
- 31,506
- φ(n) — Euler's totient
- 10,500
- Sum of prime factors
- 10,503
Primality
Prime factorization: 2 × 10501
Divisors & multiples
Sums & aliquot sequence
Representations
- In words
- twenty-one thousand two
- Ordinal
- 21002nd
- Binary
- 101001000001010
- Octal
- 51012
- Hexadecimal
- 0x520A
- Base64
- Ugo=
- One's complement
- 44,533 (16-bit)
Historical numeral systems
- Babylonian (base 60)
- 𒁹𒁹𒁹𒁹𒁹 𒌋𒌋𒌋𒌋𒌋 𒁹𒁹
- Egyptian hieroglyphic
- 𓂍𓂍𓆼𓏺𓏺
- Greek (Milesian)
- ͵καβʹ
- Mayan (base 20)
- 𝋢·𝋬·𝋪·𝋢
- Chinese
- 二萬一千零二
- Chinese (financial)
- 貳萬壹仟零貳
Digit at this position in famous constants
- π — Pi (π)
- Digit 21,002 = 8
- e — Euler's number (e)
- Digit 21,002 = 2
- φ — Golden ratio (φ)
- Digit 21,002 = 9
- √2 — Pythagoras's (√2)
- Digit 21,002 = 0
- ln 2 — Natural log of 2
- Digit 21,002 = 0
- γ — Euler-Mascheroni (γ)
- Digit 21,002 = 3
Also seen as
Goldbach's conjecture says every even integer greater than 2 is the sum of two primes. For 21002, here are decompositions:
- 19 + 20983 = 21002
- 43 + 20959 = 21002
- 73 + 20929 = 21002
- 103 + 20899 = 21002
- 193 + 20809 = 21002
- 229 + 20773 = 21002
- 271 + 20731 = 21002
- 283 + 20719 = 21002
Showing the first eight; more decompositions exist.
UTF-8 encoding: E5 88 8A (3 bytes).
As an unsigned 32-bit integer, this is the IPv4 address 0.0.82.10.
- Address
- 0.0.82.10
- Class
- reserved
- IPv4-mapped IPv6
- ::ffff:0.0.82.10
Unspecified address (0.0.0.0/8) — "this network" placeholder.
The digit sequence 21002 first appears in π at position 13,721 of the decimal expansion (the 13,721ordinal-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.