2165
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 14
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 2604
- Proper Divisor Sum (Aliquot Sum)
- 439
- 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
- 1728
- Möbius Function
- 1
- Radical
- 2165
- Omega Function (Ω)
- 2
- Little Omega Function (ω)
- 2
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
- no
- Narcissistic Number
- no
- Collatz Steps
- 45
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- Squarefree Number
- yes
- 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
- Numbers m such that Fibonacci(m) ends with m.at n=43A000350
- Coordination sequence T5 for Zeolite Code BOG.at n=33A008053
- Coordination sequence T1 for Zeolite Code MOR.at n=30A008182
- Coordination sequence T1 for Zeolite Code WEI.at n=33A009917
- Number of trees on n nodes with 3 forbidden limbs of size 4, 5 and 6.at n=12A014280
- Expansion of 1/((1-2*x)*(1-6*x)*(1-9*x)).at n=3A016306
- Numbers k such that the continued fraction for sqrt(k) has period 17.at n=16A020356
- a(n) = (d(n)-r(n))/5, where d = A026049 and r is the periodic sequence with fundamental period (4,1,4,0,1).at n=27A026051
- a(n) = n^2 + n + 3.at n=46A027688
- Number of different values of i^2 + j^2 + k^2 for i,j,k in [ 0,n ] (or [ -n,n ]).at n=34A034966
- Coordination sequence T3 for Zeolite Code SFF.at n=31A038433
- Denominators of continued fraction convergents to sqrt(745).at n=7A042435
- Numbers k such that string 6,5 occurs in the base 8 representation of k but not of k-1.at n=37A044240
- Numbers k such that the string 6,5 occurs in the base 9 representation of k but not of k-1.at n=29A044310
- Numbers n such that string 6,5 occurs in the base 10 representation of n but not of n-1.at n=23A044397
- Numbers n such that string 6,5 occurs in the base 8 representation of n but not of n+1.at n=37A044621
- Numbers n such that string 6,5 occurs in the base 9 representation of n but not of n+1.at n=29A044691
- Numbers n such that string 6,5 occurs in the base 10 representation of n but not of n+1.at n=23A044778
- a(n)=T(n+2,n), array T given by A048212.at n=41A048218
- a(n)=T(n,1)+T(n,n), array T given by A048212.at n=42A048223