5109
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 15
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 7392
- Proper Divisor Sum (Aliquot Sum)
- 2283
- 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
- 3120
- Möbius Function
- -1
- Radical
- 5109
- Omega Function (Ω)
- 3
- 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
- no
- Narcissistic Number
- no
- Collatz Steps
- 59
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- 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
- a(n) is the number of conjugacy classes in the alternating group A_n.at n=32A000702
- Coordination sequence T2 for Zeolite Code DOH.at n=44A008079
- Molien series for A_5.at n=49A008628
- Expansion of Product_{m>=1} (1-m*q^m)^-13.at n=4A022737
- a(n) = (d(n)-r(n))/2, where d = A026046 and r is the periodic sequence with fundamental period (0,1,0,1).at n=27A026047
- a(n) = (d(n)-r(n))/2, where d = A026057 and r is the periodic sequence with fundamental period (0,0,1,0).at n=32A026058
- Numbers in which all pairs of consecutive base-6 digits differ by 2.at n=47A033084
- First differences give (essentially) A028242.at n=35A035107
- Number of partitions of n into parts not of the form 21k, 21k+5 or 21k-5. Also number of partitions with at most 4 parts of size 1 and differences between parts at distance 9 are greater than 1.at n=31A035983
- Numbers whose base-4 representation contains exactly three 1's and three 3's.at n=29A045127
- Numbers k that divide 7^k + 2^k.at n=23A045580
- a(1) = 8; a(n) is smallest number >= a(n-1) such that the juxtaposition a(1)a(2)...a(n) is a prime.at n=32A046258
- a(n) = a(n-1) + a(m) for n >= 4, where m = 2^(p+1) + 2 - n and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = 1 and a(2) = a(3) = 2.at n=43A050045
- Numbers k such that 269*2^k + 1 is prime.at n=15A053351
- Numbers m such that there are precisely 3 groups of order m.at n=27A055561
- a(n) = n*(7*n^2-4)/3.at n=13A063521
- n for which floor((4/3)^n) is prime.at n=29A070762
- a(n+1) = floor((1/n)*(Sum_{k=1..n} a(k)^((n+1)/k))), given a(0)=1, a(1)=3, a(2)=8.at n=8A079121
- Numbers k for which the sums of prime factors (ignoring multiplicity) of sigma(k) and phi(k) are equal but the sets of prime factors of sigma and phi are different.at n=15A081378
- Sum of trapezoid weights of all Motzkin paths of length n.at n=9A104574