2475
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
- 2
Divisibility
- Divisor Count
- 18
- Divisor Sum
- 4836
- Proper Divisor Sum (Aliquot Sum)
- 2361
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 1200
- Möbius Function
- 0
- Radical
- 165
- Omega Function (Ω)
- 5
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 71
- Smith Number
- yes
- 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
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Number of monosubstituted alkanes C(n-1)H(2n-1)-X with n-1 carbon atoms that are not stereoisomers.at n=17A000621
- Positions of remoteness 3 in Beans-Don't-Talk.at n=28A005695
- a(n) = n^2*(n^2 - 1)/4.at n=10A006011
- a(n) = floor(n*(n+2)*(2*n-1)/8).at n=20A007518
- Triangle of D'Arcais numbers.at n=17A008298
- a(n) = n^2 - floor( n/2 ).at n=50A014848
- Numbers k such that phi(k) + 9 | sigma(k).at n=3A015800
- a(n)-th nonsquarefree is sum of first k nonsquarefrees for some k.at n=30A020644
- Numbers k such that k and 3*k are anagrams.at n=2A023087
- Base 6 expansion uses each positive digit just once.at n=19A023744
- a(n) = (d(n)-r(n))/2, where d = A026037 and r is the periodic sequence with fundamental period (1,0,0,1).at n=22A026038
- a(n) = sum of the numbers between the two n's in A026346.at n=32A026349
- Sequence satisfies T^2(a)=a, where T is defined below.at n=45A027590
- a(n) = 9*(n+1)*binomial(n+2,9)/2.at n=2A027782
- a(n) = (1/4)*floor(n/2)*floor((n-1)/2)*floor((n-2)/2)*floor((n-3)/2).at n=22A028723
- Numbers k that divide the (right) concatenation of all numbers <= k written in base 25 (most significant digit on left).at n=34A029470
- Intermediate edge b of smallest (measured by the longest edge) primitive Euler bricks (a, b, c, sqrt(a^2 + b^2), sqrt(b^2 + c^2), sqrt(a^2 + c^2) are integers).at n=9A031174
- Number of aperiodic necklaces of n beads of 10 colors.at n=3A032165
- a(n) = 11*n^2.at n=15A033584
- a(n) = n*(4*n-1).at n=25A033991