14121
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 9
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 20960
- Proper Divisor Sum (Aliquot Sum)
- 6839
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 9396
- Möbius Function
- 0
- Radical
- 1569
- Omega Function (Ω)
- 4
- 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
- yes
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 151
- 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) = 2*a(n-1) + 5*a(n-2), a(0) = 0, a(1) = 1.at n=9A002532
- Numbers k that divide s(k), where s(1)=1, s(j)=19*s(j-1)+j.at n=24A014869
- Numbers whose product of decimal digits equals its sum of binary digits.at n=25A064003
- Coefficient of x^n in A(x)^n is A087457(n) for n>=1.at n=8A088929
- a(n) = Sum_{k=1..n} C(n-1,k-1) * S2(n,k) for n>0, a(0)=1, where S2(n,k) = A048993(n,k) are Stirling numbers of the 2nd kind.at n=7A134055
- Composite numbers whose product of digits is 8.at n=41A201056
- Number of (w,x,y,z) with all terms in {1,...,n} and w*x < 2*y*z.at n=12A211795
- Number of binary arrays indicating the locations of trailing edge maxima of a random length-n 0..4 array extended with zeros and convolved with 1,2,2,1.at n=20A222107
- Triangle T(n,k) read by rows: T(n,k) = number of permutations on 123...n with exactly two abc patterns and no aj pattern with j<=k, for n>=0, 0<=k<=n.at n=58A229158
- a(n) = n*prime(prime(n)) - prime(n).at n=25A230285
- The number of tilings of a 7 X (4n) floor with 1 X 4 tetrominoes.at n=5A236581
- Composite numbers whose sum of aliquot parts divides the sum of their unrelated numbers.at n=8A250399
- Number of length 3 1..(n+1) arrays with every leading partial sum divisible by 2, 3, 5 or 7.at n=30A258634
- Triangle read by rows, T(n, k) = Sum_{j=0..n} (-1)^(n-j)*C(-j, -n)*S2(k, j), S2 the Stirling set numbers A048993, for n >= 0 and 0 <= k <= n.at n=35A271701
- Number of active (ON, black) cells at stage 2^n-1 of the two-dimensional cellular automaton defined by "Rule 613", based on the 5-celled von Neumann neighborhood.at n=6A273242
- Least numbers k that can be expressed as k = a' + b', with k = a + b, in exactly n ways, where a' and b' are the arithmetic derivatives of a and b.at n=5A292362
- A(n, k) is the smallest number x > A(n, k-1) such that every letter, with repetition, that occurs in the English name of A(n, k-1) also occurs in the English name of x, with A(n, 1) = n; square array, read by antidiagonals downwards.at n=29A303380
- Square array A(n,k), n >= 0, k >= 0, read by antidiagonals downwards, where column k is the expansion of e.g.f. B(x)^k, where B(x) is the e.g.f. of A384720.at n=32A384722
- Number of integer partitions of n whose first differences are not all distinct.at n=35A389919