13447
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 16416
- Proper Divisor Sum (Aliquot Sum)
- 2969
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 10752
- Möbius Function
- -1
- Radical
- 13447
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 213
- 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) = (8*n+1)*(8*n+7).at n=14A001533
- 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=39A026047
- Expansion of (1 + 2*x) / (1 - x - 4*x^2).at n=10A026581
- Number of partitions of n into parts 3k and 3k+1 with at least one part of each type.at n=50A035618
- Numerators of continued fraction convergents to sqrt(83).at n=3A041146
- Numerators of continued fraction convergents to sqrt(332).at n=7A041626
- Numerators of continued fraction convergents to sqrt(747).at n=3A042438
- Number of monic polynomials with integer coefficients of degree n with all roots in unit disc.at n=15A051894
- a(0) = 1, a(1) = 7; for n>=2 a(n) is the number of degree-n monic reducible polynomials over GF(7), i.e., a(n) = 7^n - A001693(n).at n=5A058822
- Sums of members of groups in A076062.at n=29A076060
- Shallow diagonal of triangular spiral in A051682.at n=27A081275
- A sequence generated from the Narayana triangle considered as a matrix, or from Pascal's triangle.at n=6A095266
- Numbers k such that 8*10^k - 9 is prime.at n=21A103068
- Number of compositions of n into a square number of parts.at n=17A103198
- Least k such that the difference between consecutive semiprimes A065516(k) equals n, or 0 if no such k exists.at n=25A123375
- a(n) = 343*n - 273.at n=39A157369
- a(n) = 13122*n^2 + 324*n + 1.at n=0A157506
- a(n) = 8*n^2 - 1.at n=40A157914
- Nonnegative values x of solutions (x, y) to the Diophantine equation x^2+(x+113)^2 = y^2.at n=9A161478
- Composite squarefree numbers n such that p(i)+7 divides n-7, where p(i) are the prime factors of n.at n=4A225717