13995
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 27
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 24336
- Proper Divisor Sum (Aliquot Sum)
- 10341
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 7440
- Möbius Function
- 0
- Radical
- 4665
- 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
- no
Recreational
- Happy Number
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 120
- 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
- a(n) = (d(n)-r(n))/2, where d = A026049 and r is the periodic sequence with fundamental period (1,0,0,1).at n=39A026050
- T(2n+3, n), array T as in A051168; a count of Lyndon words.at n=9A050181
- O.g.f.: A(x) = Sum_{n>=0} x^n*Product_{k=0..n} (1 + k*x).at n=11A124380
- Subtriangle of triangle in A051168: remove central column of A051168 and all columns to the right; now read by upwards diagonals.at n=68A130513
- Keith sequence for the number 197.at n=14A186830
- Triangle read by rows: entries on or below the main diagonal in A245558.at n=74A245559
- Number of 3-ary plane multitrees with n edges.at n=9A246974
- Concatenate the n-th prime with the n-th semiprime.at n=33A262428
- a(n) = a(n-7) + a(n-4) + a(n-1) for n>1 and a(n)=1 for n<=1.at n=25A262602
- Number of aperiodic necklaces (Lyndon words) with 9 black beads and n white beads.at n=12A263318
- q-Expansion of wedge character chi^(3)(q).at n=19A288579
- Partial sums of A299266.at n=26A299267
- Evaluation of the Little-Schröder polynomials at 1/2 and normalized with 2^n.at n=5A331328
- Odd binary Niven numbers (A144302) k such that k/wt(k) is also an odd binary Niven number, where wt(k) = A000120(k) is the binary weight of k.at n=36A376618
- Index where prime(n) appears as a term in A379442.at n=50A379558
- a(n) = Sum_{k=0..n} |Stirling1(n+k,2*k)|.at n=6A392744