2439
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
- 3
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 3536
- Proper Divisor Sum (Aliquot Sum)
- 1097
- 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
- 1620
- Möbius Function
- 0
- Radical
- 813
- Omega Function (Ω)
- 3
- 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
- 133
- 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
- no
- Odd
- yes
Appears in sequences
- Numbers of the form (p^2 - 1)/120 where p is 1 or prime.at n=48A002381
- Number of bipartite partitions.at n=12A002762
- Expansion of g.f.: x^4/((1-x)*(1-x^2)^2*(1-x^3)).at n=56A008763
- Expansion of (1+x^4)/((1-x)*(1-x^2)*(1-x^3)*(1-x^4)).at n=53A008765
- Expansion of (1+x^11)/((1-x)*(1-x^2)*(1-x^3)*(1-x^4)).at n=56A008772
- Coordination sequence T5 for Zeolite Code TER.at n=33A016437
- Number of partitions of n into parts having a common factor.at n=52A018783
- Numbers k such that the continued fraction for sqrt(k) has period 24.at n=43A020363
- a(n) = n*(15*n + 1)/2.at n=18A022273
- a(0)=a(1)=3; thereafter a(n) = a(n-1) + a(n-2) + 1.at n=14A022403
- a(0)=3, a(1)=7; thereafter a(n) = a(n-1) + a(n-2) + 1.at n=13A022406
- Numbers k such that Fibonacci(k) == 34 (mod k).at n=23A023180
- a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n+1-k), where k = [ (n+1)/2 ], s = (Fibonacci numbers), t = A014306.at n=30A024467
- Index of 7^n within the sequence of the numbers of the form 2^i*7^j.at n=41A025720
- a(n) = T(n,n-2), where T is the array in A026386.at n=46A026393
- a(n) = position of the n-th n in A026400.at n=45A026403
- a(n) = Sum{T(i,j)}, 0<=j<=i, 0<=i<=n, T given by A026907.at n=5A026917
- Divisors of 99999.at n=8A027893
- Divisors of 9999999999.at n=13A027895
- Lucky numbers with size of gaps equal to 12 (upper terms).at n=28A031895