9506
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 16758
- Proper Divisor Sum (Aliquot Sum)
- 7252
- 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
- 4032
- Möbius Function
- 0
- Radical
- 1358
- Omega Function (Ω)
- 4
- 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
- yes
Recreational
- Happy Number
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 52
- 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
- no
- Carmichael Number
- no
Classification
- Even
- yes
- Odd
- no
Appears in sequences
- a(n) = (3*n+1)*(3*n+2).at n=32A001504
- G.f.: (1 + x^3 + x^4 + ... + x^12 + x^15)/Product_{i=1..10} (1 - x^i).at n=28A003403
- a(n) = Sum_{k>=1} floor( 2*(1+sqrt(2))^(n-k) ).at n=9A020963
- Sequence satisfies T^2(a)=a, where T is defined below.at n=46A027593
- Numbers whose set of base-13 digits is {3,4}.at n=26A032837
- Product of a prime and the following number.at n=24A036690
- Numbers k such that 80*R_k + 1 is prime, where R_k = 11...1 is the repunit (A002275) of length k.at n=12A056664
- If D[n] is divisor-set of n, then in set of 1+D only 2 primes occur:{2,3}; also n is not squarefree.at n=28A072607
- Maximum of A073830(k) for k between A001359(n) and A001359(n+1).at n=7A073831
- a(n) = sqrt(A076967(n)).at n=25A076968
- Deficient oblong numbers.at n=15A077804
- Number of unlabeled and connected graphs on n vertices which are either bipartite or co-bipartite.at n=9A079565
- Numbers k such that A000984(k) mod k = 0 and A080383(k) != 7.at n=41A080392
- Numbers k such that the largest prime power factor of k equals floor(sqrt(k)).at n=39A081807
- Number of compositions of n into 4 parts such that no two adjacent parts are equal.at n=36A106353
- Odious oblong (promic) numbers.at n=38A130201
- a(n) = (4*n+1)*(4*n+2) = (4*n+2)!/(4*n)!.at n=24A157870
- Number of binary strings of length n with no substrings equal to 0001 1010 or 1101.at n=15A164488
- a(1)=3 and a(n)=Floor[1/(n-1)^2 * a(n-1)^2].at n=6A176163
- a(n) = 25*n^2 + 25*n + 6.at n=19A177059