6180
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 15
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 24
- Divisor Sum
- 17472
- Proper Divisor Sum (Aliquot Sum)
- 11292
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 1632
- Möbius Function
- 0
- Radical
- 3090
- Omega Function (Ω)
- 5
- Little Omega Function (ω)
- 4
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
- 62
- 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
- a(n) = 1 + n/2 + 9*n^2/2.at n=37A006137
- Theta series of A_5 lattice.at n=34A008445
- Rectilinear crossing number of complete graph on n nodes.at n=26A014540
- Number of lines through exactly 7 points of an n X n grid of points.at n=52A018814
- Number of 6's in all partitions of n.at n=34A024790
- Numbers having three 4's in base 8.at n=32A043439
- a_{k+1} = 6*a_k + 11*a_{k-1} - 19*a_{k-2} - 4*a_{k-3} + a_{k-4}, a_1=1, a_2=2, a_3=19, a_4=118, a_5=875.at n=5A055518
- Dimension of the space of weight n cuspidal newforms for Gamma_1( 73 ).at n=28A063346
- Least m such that one less than m-th prime has n divisors (or 0 if no such prime exists).at n=50A072275
- Irregular array, read by rows: T(n,k) is the number of labeled acyclic digraphs with n nodes and k arcs (n >= 0, 0 <= k <= n*(n-1)/2).at n=20A081064
- Least positive integers, all distinct, that satisfy sum(n>0,1/a(n)^z)=0, where z=(60+I*11)/61.at n=18A084804
- Smallest number a(n) > n such that a(n)! contains n! as a substring.at n=13A086654
- Bisection of A088567.at n=49A088585
- Graham-Pollak sequence with initial term 8.at n=19A091523
- Numbers n such that phi(n)=2*reversal(n).at n=0A114930
- Coordination sequence for 8-dimensional cyclotomic lattice Z[zeta_20].at n=4A126901
- Integers of the form sum_{i=2521..j} i/(i-2520) for any upper limit j.at n=5A144971
- Number of consistent sets of 5 irreflexive binary order relationships over n objects.at n=1A147821
- a(n) = 250*n - 70.at n=25A154361
- Triangle read by rows: T(n,k) is the number of permutations of [n] having no 3-sequences and having k successions (0 <= k <= floor(n/2)); a succession of a permutation p is a position i such that p(i +1) - p(i) = 1.at n=28A180185