12736
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
- 3
Divisibility
- Divisor Count
- 14
- Divisor Sum
- 25400
- Proper Divisor Sum (Aliquot Sum)
- 12664
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 6336
- Möbius Function
- 0
- Radical
- 398
- Omega Function (Ω)
- 7
- 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
- no
- Harshad Number
- no
- 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
- yes
- Odd
- no
Appears in sequences
- Aliquot sequence starting at 180.at n=14A008891
- G.f. satisfies A(x) = 1 + x*cycle_index(G,A(x)) where G = tetragonal pyramid group of order 4 with cycle index (z1^5+2*z1*z4+z1*z2^2)/4.at n=8A036783
- Numbers k such that k divides the (right) concatenation of all numbers <= k written in base 11 (most significant digit on right).at n=17A061940
- Numbers n such that n and 2^n end with the same three digits.at n=12A067866
- Expansion of 1/(1-2*x+2*x^2+2*x^3).at n=18A077945
- Expansion of 1/(1+2*x+2*x^2-2*x^3).at n=18A077991
- Array read by antidiagonals: see A128195 for details.at n=39A126062
- Number of binary strings of length n with equal numbers of 0110 and 1001 substrings.at n=15A164177
- Total number of repeated parts in all partitions of n.at n=25A194452
- Number of n X 2 0..3 arrays with no element equal to another within two positions in the same row or column, and new values 0..3 introduced in row major order.at n=8A206687
- T(n,k)=Number of nXk 0..3 arrays with no element equal to another within two positions in the same row or column, and new values 0..3 introduced in row major order.at n=46A206692
- T(n,k)=Number of nXk 0..2 arrays with no element equal to a different number of vertical neighbors than horizontal neighbors, with new values 0..2 introduced in row major order.at n=46A240893
- T(n,k)=Number of nXk 0..2 arrays with no element equal to one or three horizontal or vertical neighbors, with new values 0..2 introduced in row major order.at n=46A241108
- Numbers n such that the smallest prime divisor of n^2+1 is 101.at n=42A248553
- Number of length n+5 0..1 arrays with at most one downstep in every 5 consecutive neighbor pairs.at n=11A255989
- Number of (3+1)X(n+1) arrays of permutations of 0..n*4+3 with each element having directed index change 0,1 1,0 2,1 or -1,-1.at n=9A264477
- Let s(k) denote the sum of the even proper divisors of k. The sequence lists the pairs of numbers (x, y) such that s(x) = y and s(y) = x.at n=9A279812
- List of ordered pairs (x, y) from A279812.at n=9A279950
- Expansion of (1 + x) * Product_{k>=1} (1 + x^k)/(1 - x^k).at n=20A309266
- E.g.f.: C(x,q) = 1 + Integral S(x,q) * C(q*x,q) dx, such that C(x,q)^2 - S(x,q)^2 = 1, where C(x,q) = Sum_{n>=0} sum_{k=0..n*(n-1)/2} T(n,k)*x^n*y^k/n!, as an irregular triangle of coefficients T(n,k) read by rows.at n=19A322218