21870 (number)
21,870 (twentyone thousand eight hundred seventy) is an even fivedigits composite number following 21869 and preceding 21871. In scientific notation, it is written as 2.187 × 10^{4}. The sum of its digits is 18. It has a total of 9 prime factors and 32 positive divisors. There are 5,832 positive integers (up to 21870) that are relatively prime to 21870.
Basic properties
 Is Prime? No
 Number parity Even
 Number length 5
 Sum of Digits 18
 Digital Root 9
Name
Short name  21 thousand 870 

Full name  twentyone thousand eight hundred seventy 
Notation
Scientific notation  2.187 × 10^{4} 

Engineering notation  21.87 × 10^{3} 
Prime Factorization of 21870
Prime Factorization 2 × 3^{7} × 5
Composite numberω(n)  Distinct Factors  3  Total number of distinct prime factors 

Ω(n)  Total Factors  9  Total number of prime factors 
rad(n)  Radical  30  Product of the distinct prime numbers 
λ(n)  Liouville Lambda  1  Returns the parity of Ω(n), such that λ(n) = (1)^{Ω(n)} 
μ(n)  Mobius Mu  0  Returns:

Λ(n)  Mangoldt function  0  Returns log(p) if n is a power p^{k} of any prime p (for any k >= 1), else returns 0 
The prime factorization of 21,870 is 2 × 3^{7} × 5. Since it has a total of 9 prime factors, 21,870 is a composite number.
Divisors of 21870
32 divisors
τ(n)  Total Divisors  32  Total number of the positive divisors of n 

σ(n)  Sum of Divisors  59040  Sum of all the positive divisors of n 
s(n)  Aliquot Sum  37170  Sum of the proper positive divisors of n 
A(n)  Arithmetic Mean  1845  Returns the sum of divisors (σ(n)) divided by the total number of divisors (τ(n)) 
G(n)  Geometric Mean  147.88509052639  Returns the nth root of the product of n divisors 
H(n)  Harmonic Mean  11.853658536585  Returns the total number of divisors (τ(n)) divided by the sum of the reciprocal of each divisors 
The number 21,870 can be divided by 32 positive divisors (out of which 16 are even, and 16 are odd). The sum of these divisors (counting 21,870) is 59,040, the average is 1,845.
Other Arithmetic Functions (n = 21870)
φ(n)  Euler Totient  5832  Total number of positive integers not greater than n that are coprime to n 

λ(n)  Carmichael Lambda  2916  Smallest positive number such that a^{λ(n)} ≡ 1 (mod n) for all a coprime to n 
π(n)  Prime Pi  ≈ 2453  Total number of primes less than or equal to n 
r_{2}(n)  Sum of 2 squares  0  The number of ways n can be represented as the sum of 2 squares 
There are 5,832 positive integers (less than 21,870) that are coprime with 21,870. And there are approximately 2,453 prime numbers less than or equal to 21,870.
Divisibility of 21870
m  2  3  4  5  6  7  8  9 

n mod m  0  0  2  0  0  2  6  0 
The number 21,870 is divisible by 2, 3, 5, 6 and 9.
Classification of 21870
By Arithmetic functions
 Arithmetic
 Abundant
Expressible via specific sums
 Polite
 Practical
Other numbers
 Frugal
 Regular
Base conversion (21870)
Base  System  Value 

2  Binary  101010101101110 
3  Ternary  1010000000 
4  Quaternary  11111232 
5  Quinary  1144440 
6  Senary  245130 
8  Octal  52556 
10  Decimal  21870 
12  Duodecimal  107a6 
16  Hexadecimal  556e 
20  Vigesimal  2eda 
36  Base36  gvi 
Basic calculations (n = 21870)
Multiplication
n×yn×2  43740 

n×3  65610 
n×4  87480 
n×5  109350 
Division
n÷yn÷2  10935.000 

n÷3  7290.000 
n÷4  5467.500 
n÷5  4374.000 
Exponentiation
n^{y}n^{2}  478296900 

n^{3}  10460353203000 
n^{4}  228767924549610000 
n^{5}  5003154509899970700000 
Nth Root
^{y}√n^{2}√n  147.88509052639 

^{3}√n  27.965092553585 
^{4}√n  12.160801393263 
^{5}√n  7.3785284575481 
21870 as geometric shapes
Circle
Radius = nDiameter  43740 

Circumference  137413.26266802 
Area  1502614027.2748 
Sphere
Radius = nVolume  43816225035332 

Surface area  6010456109.0991 
Circumference  137413.26266802 
Square
Length = nPerimeter  87480 

Area  478296900 
Diagonal  30928.8506091 
Cube
Length = nSurface area  2869781400 

Volume  10460353203000 
Space diagonal  37879.951161531 
Equilateral Triangle
Length = nPerimeter  65610 

Area  207108632.97567 
Altitude  18939.975580766 
Triangular Pyramid
Length = nSurface area  828434531.90269 

Volume  1232764447241.3 
Height  17856.780224889 
Cryptographic Hash Functions
md5  3ac44bdb7fb0bbd5c8b3f4db0218d05e 

sha1  af24b9d3e476a0a727e4f7f83b72c5f6efa9a840 
sha256  4c5605c21eb08fd736fa7765282bbc2dffa5025c97b72ab64d7ae5cbcae8ec15 
sha512  3a083fa70b7a3a5c69f7b3d519a0bafce179a4b875ab8aef3071a95d866799cb259bddc31cda712d2a5e89c4c1433dd9ba295116302e20e9137ab1bb88e61b04 
ripemd160  f5b2ddab28b33a5f804077c1339d0639f0c3e3d2 