13961
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 14592
- Proper Divisor Sum (Aliquot Sum)
- 631
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 13332
- Möbius Function
- 1
- Radical
- 13961
- 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
- 89
- 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
- 30*a(n) is the gap between sexy prime triples in the n-th sexy prime triple triple whose initial term is 7.at n=14A090776
- a(n) is the least odd composite number m such that nextprime(p*m) > p*nextprime(m) where p is the n-th prime.at n=9A117103
- a(n) = 15*n*(n+1) + 11.at n=30A132208
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, 0, 1), (-1, 1, 1), (0, -1, 1), (1, 0, -1), (1, 0, 1)}.at n=8A149395
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 0), (-1, 0, 1), (0, 0, -1), (1, 0, 1), (1, 1, 1)}.at n=7A150948
- Number of -n..n arrays x(0..3) of 4 elements with zero sum and no element more than one greater than the previous.at n=36A199848
- Number of 0..n arrays of length 4 with 0 never adjacent to n.at n=9A212837
- Numbers k such that 3^k + k^3 - 1 is prime.at n=13A215440
- Number of length n+2 0..4 arrays with some pair in every consecutive three terms totalling exactly 4.at n=5A245865
- T(n,k)=Number of length n+2 0..k arrays with some pair in every consecutive three terms totalling exactly k.at n=41A245869
- Number of length 6+2 0..n arrays with some pair in every consecutive three terms totalling exactly n.at n=3A245875
- Numbers of words on alphabet {0,1,...,10} with no subwords ii, for i from {0,1}.at n=4A254600
- Expansion of psi(x^3)^3 / (psi(x)^2 * psi(x^2)) in powers of x where psi() is a Ramanujan theta function.at n=42A262157
- Number of symmetric linked diagrams with n links and no simple link.at n=9A271218
- Expansion of 1/(1 - x*Product_{k>=1} (1 - x^k)^k).at n=23A299211
- Number T(n,k) of colored integer partitions of n using all colors of a k-set such that parts i have distinct color patterns in arbitrary order and each pattern for a part i has i colors in (weakly) increasing order; triangle T(n,k), n>=0, 0<=k<=n, read by rows.at n=48A309973
- a(n) = Sum_{k=1..n} (A000292(n) mod A000217(k)).at n=53A344435
- Number of growing self-avoiding walks of length n on a half-infinite strip of height 3 with a trapped endpoint.at n=15A374297
- Numbers k such that primorial base expansion of A276086(k) has the primorial base expansion of A003415(k) as its suffix, where A003415 is the arithmetic derivative, and A276086 is the primorial base exp-function.at n=18A383933