12501
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
- 18560
- Proper Divisor Sum (Aliquot Sum)
- 6059
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 8316
- Möbius Function
- 0
- Radical
- 1389
- 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
- 125
- 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
- 4-dimensional centered tetrahedral numbers.at n=15A008498
- [ n(n-1)(n-2)(n-3)/17 ].at n=23A011927
- A convolution triangle of numbers obtained from A036068.at n=23A030524
- Numbers k such that k^4 == 1 (mod 5^5).at n=16A056102
- Number of fullerenes with 2n vertices (or carbon atoms), counting enantiomorphic pairs as distinct.at n=24A057210
- a(n) = (1/n!)*A001688(n).at n=9A094793
- a(1) = 1+2-3 = 0, a(2) = 4+5+6-7 = 8, a(3) = 8+9+10+11-12 = 26, a(4) = 13+14+15+16+17-18 = 57, ...at n=27A111694
- A 'Morgan Voyce' transform of the large Schroeder numbers A006318.at n=6A155867
- Triangle T(n,k) read by rows: T(n,k) = (k-1)*T(n-1,k) + (n-k+2)*T(n-1, k-1), with T(n,1)=1, for 1 <= k <= n, n >= 1.at n=31A157011
- a(n) = 625*n + 1.at n=19A158383
- a(n) = 20*n^2 + 1.at n=25A158493
- Sum of all repeated parts of all partitions of n.at n=20A163986
- a(n) = (n+8)*a(n-1) + (n-1)*a(n-2), a(-1)=0, a(0)=1.at n=4A176735
- E.g.f. satisfies: A(x) = exp( x/(1 - x*A'(x)/A(x)) ).at n=5A182962
- a(n) = 4*5^n + 1.at n=5A199215
- a(n) = 5*n^2 + 1.at n=50A212656
- a(n) = Sum_{d|n} d^n * phi(d), where phi(n) is the Euler totient function A000010(n).at n=4A226561
- E.g.f.: exp(Sum_{n>=1} n*A000041(n)*x^n), where A000041(n) is the number of partitions of n.at n=5A293731
- Square array A(n,k), n >= 0, k >= 0, read by antidiagonals, where column k is the expansion of e.g.f.: exp(Sum_{j>=1} j^(k-1)*A000041(j)*x^j).at n=33A293796
- Expansion of Product_{k>=1} 1/(1 - Sum_{j=1..k} x^(j*k)).at n=25A319758