12525
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 15
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 20832
- Proper Divisor Sum (Aliquot Sum)
- 8307
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 6640
- Möbius Function
- 0
- Radical
- 2505
- 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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 112
- 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
- Numbers k such that 1 + binomial(k,j) is prime for only 2 values of j (0 <= j <= k).at n=38A067317
- Numbers k such that the "inventory" A063850 of k is a perfect square.at n=13A079465
- Triangle read by rows: T(n,k) is the number of peakless Motzkin paths of length n containing k subwords of the type U H^j U or D H^j D for some j>0, where U=(1,1), H=(1,0) and D=(1,-1) (can be easily expressed using RNA secondary structure terminology).at n=49A097100
- a(n) = Sum_{k=0..n} C(n,k)^2*(n-k)!*k^3.at n=5A105218
- a(n) = Fibonacci(n) mod n^3.at n=24A132636
- Number of (n+1) X 5 0..2 arrays with all 2 X 2 subblock sums the same.at n=5A183998
- Number of (n+1) X 7 0..2 arrays with all 2 X 2 subblock sums the same.at n=3A184000
- T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with all 2X2 subblock sums the same.at n=39A184003
- Number of peakless Motzkin paths of length n containing no subwords of type uh^ju or dh^jd (j>=1), where u=(1,1), h=(1,0), and d=(1,-1) (can be easily expressed using RNA secondary structure terminology).at n=16A190160
- Number of nX2 0..4 arrays with every row and column nondecreasing rightwards and downwards, and the number of instances of each value within one of each other.at n=26A200984
- Number of partitions of n containing at least one part m-6 if m is the largest part.at n=34A212546
- Concatenation of n^3 and n^2.at n=4A239461
- G.f.: Sum_{n>=0} x^n / (1-x^2)^(2*n+1) * [Sum_{k=0..n} C(n,k)^2 * x^k] * [Sum_{k=0..n} C(n,k)^2 * x^(2*k)].at n=9A246653
- Least positive integer m such that m + n divides pi(m)^2 + pi(n)^2, where pi(x) denotes the number of primes not exceeding x.at n=31A248044
- Numbers k such that (37*10^k + 377)/9 is prime.at n=16A293852
- Triangle read by rows: T(n,m) = Sum_{k=m+1..n} (n-1)!/(k-1)!*binomial(2*n-k-1, n-1)*E(k,m) where E(n,m) is Euler's triangle A173018, T(0,0) = 1, n >= m >= 0.at n=41A316773
- Square array T(n,k), n >= 0, k >= 0, read by antidiagonals, where T(n,k) = Sum_{j=0..n} j^k * (n-j)! * binomial(n,j)^2.at n=41A341200
- Expansion of (1/x) * Series_Reversion( x / ((1+x)^3 * C(x)) ), where C(x) is the g.f. of A000108.at n=5A381882