13024
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 10
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 24
- Divisor Sum
- 28728
- Proper Divisor Sum (Aliquot Sum)
- 15704
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 5760
- Möbius Function
- 0
- Radical
- 814
- Omega Function (Ω)
- 7
- 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
- 45
- 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
- Number of augmented André 3-signed permutations: E.g.f. (1-sin(3*x))^(-1/3).at n=6A007788
- a(n) = n*(19*n + 1)/2.at n=37A022277
- Positive numbers k such that k and 3*k are anagrams in base 6 (written in base 6).at n=10A023065
- T(2n,n+4), T given by A026747.at n=5A026864
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 57.at n=25A031555
- LCM-convolution of squares A000290 with themselves.at n=13A033456
- For each prime p take the sum of nonprimes < p.at n=41A045717
- (1/18)*Difference between concatenation of n and n^2 and concatenation of n^2 and n.at n=36A055435
- Numbers k such that phi(x) = k has exactly 12 solutions.at n=40A060675
- A014486-indices of A083932-trees.at n=32A083934
- a(n) = (5/6)*n^3+(5/2)*n^2+(8/3)*n.at n=24A092185
- Numbers k such that 10^k + 5*R_k - 2 is prime, where R_k = 11...1 is the repunit (A002275) of length k.at n=6A102936
- Expansion of 1/sqrt(1-8x-8x^2).at n=5A106258
- Let n = a_1a_2...a_k, where the a_i are digits. a(n) = least multiple of n of the type b_1a_1b_2a_2...a_kb_{k+1}, obtained by inserting single digits b_i in the gaps and both ends; 0 if no such number exists.at n=31A110735
- Moessner triangle based on primes.at n=21A125312
- a(n) = first term that can be reduced in n steps via repeated interpretation of a(n) as a base b+1 number where b is the largest digit of a(n), such that b is always 4 so that each interpretation is base 5. Terms already fully reduced (i.e., single digits) are excluded.at n=5A141838
- Given a set of positive integers A={1,2,...,n-1,n}, n>=2. Take subsets of A of the form {1,...,n} so only subsets containing numbers 1 and n are allowed. Then a(1)=1 and a(n) is the number of subsets where arithmetic mean of the subset is an integer.at n=18A147980
- Similar to A072921 but starting with 2.at n=45A152231
- Sums of the antidiagonals of Sundaram's sieve (A159919).at n=31A159920
- Numbers k such that k^2 + 1 = p*q, p and q primes and |p-q| is square.at n=27A187401