12551
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 14
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 15744
- Proper Divisor Sum (Aliquot Sum)
- 3193
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 9720
- Möbius Function
- -1
- Radical
- 12551
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 156
- 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
- 10-gonal (or decagonal) pyramidal numbers: a(n) = n*(n + 1)*(8*n - 5)/6.at n=21A007585
- Number of partitions of n into 10 unordered relatively prime parts.at n=38A023030
- a(n) = 1*t(n) + 2*t(n-1) + ... + k*t(n+1-k), where k=floor((n+1)/2) and t(n)=2*n+1 (odd numbers).at n=40A023865
- a(n) = floor((3rd elementary symmetric function of 2,3,...,n+3)/(2+3+...+n+3)).at n=20A024178
- Numbers k such that the least term in the periodic part of the continued fraction for sqrt(k) is 32.at n=6A031710
- a(n) = A077702(n+1)/A077702(n).at n=16A077703
- a(n) = A088418(n+1)/A088418(n).at n=16A088419
- a(n) = Sum_{k>=0} k^n*A000045(k)/2^(k+1).at n=4A098799
- a(n) = 49*n^2 + 7.at n=15A158481
- Magnetic Tower of Hanoi, number of moves of disk number k, optimally solving the [RED ; NEUTRAL ; NEUTRAL] or [NEUTRAL ; NEUTRAL ; BLUE] pre-colored puzzle.at n=10A183115
- Triangle read by rows: T(n,k) (n>=1, 1 <= k <= n) = number of n-element unlabeled interval posets of height k.at n=39A193387
- Odd decagonal pyramidal numbers.at n=10A218330
- Number of n X 4 integer arrays with each element equal to the number of horizontal and antidiagonal neighbors not equal to itself.at n=15A265988
- Decimal representation of the x-axis, from the origin to the right edge, of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 270", based on the 5-celled von Neumann neighborhood.at n=13A280467
- Least number x such that x^n has n digits equal to k. Case k = 6.at n=21A285453
- a(n) = a(n-1) + a(n-2) + a([n/2]), where a(0) = 1, a(1) = 1, a(2) = 1.at n=19A298338
- Sum of piles of first n primes: a(n) = Sum(prime(i)*(2*i-1): 1<=i<=n).at n=17A316322
- Number of compositions of n whose run-lengths are not weakly increasing.at n=15A332871