8640
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 56
- Divisor Sum
- 30480
- Proper Divisor Sum (Aliquot Sum)
- 21840
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 2304
- Möbius Function
- 0
- Radical
- 30
- Omega Function (Ω)
- 10
- Little Omega Function (ω)
- 3
Special
- Factorial
- no
- Catalan Number
- no
- Bell Number
- no
- Motzkin Number
- no
- Primorial
- no
Figurate Numbers
- Fibonacci Number
- no
- Triangular Number
- no
- Perfect Square
- no
- Perfect Cube
- no
- Pentagonal Number
- no
- Hexagonal Number
- no
- Lucas Number
- no
- Tetrahedral Number
- no
- Pell Number
- no
- Tribonacci Number
- no
- Pronic Number
- no
Recreational
- Happy Number
- no
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 47
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- Prime Power
- no
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Perfect Power
- no
- Smooth Number
- yes
- Carmichael Number
- no
Classification
- Even
- yes
- Odd
- no
Appears in sequences
- Index of (the image of) the modular group Gamma(n) in PSL_2(Z).at n=29A001766
- Values of phi(k) when phi(k) = phi(k+1).at n=20A003275
- Number of fixed properly-4-dimensional polyominoes with n cells.at n=5A006764
- Molien series for alternating group Alt_8 (or A_8).at n=39A008631
- Theta series of direct sum of 2 copies of f.c.c. lattice.at n=19A008663
- a(n) = n!*(n+2)!/2.at n=4A010791
- a(n) is nonsquarefree and is sum of first k nonsquarefrees for some k.at n=36A013935
- Even octagonal numbers: a(n) = 4*n*(3*n-1).at n=27A014642
- Pisot sequence T(3,5).at n=20A020745
- Pisot sequence T(5,8), a(n) = floor(a(n-1)^2/a(n-2)).at n=19A020749
- n written in fractional base 10/8.at n=30A024663
- Theta series of 10-dimensional lattice (C6 X SU(4,2)):C2 with minimal norm 4.at n=5A029770
- Number of identity bracelets with n labeled beads of 4 colors.at n=4A032339
- Highly factorable numbers: numbers with a record number of proper factorizations.at n=31A033833
- Maximal value of d(x) (the number of divisors of x, A000005) if the binary order (see A029837) of x, the value g(x) = n.at n=42A036451
- Triangle whose (i,j)-th entry is binomial(i,j)*2^(i-j)*6^j.at n=23A038212
- Triangle whose (i,j)-th entry is binomial(i,j)*2^(i-j)*6^j.at n=18A038212
- Triangle whose (i,j)-th entry is binomial(i,j)*6^(i-j)*2^j.at n=25A038256
- Triangle whose (i,j)-th entry is binomial(i,j)*6^(i-j)*2^j.at n=17A038256
- Triangle whose (i,j)-th entry is binomial(i,j)*6^(i-j)*10^j.at n=11A038264