5580
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 36
- Divisor Sum
- 17472
- Proper Divisor Sum (Aliquot Sum)
- 11892
- 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
- 1440
- Möbius Function
- 0
- Radical
- 930
- Omega Function (Ω)
- 6
- 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
- 129
- 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) = n*(n + 1)*(n^2 - 3*n + 6)/8.at n=14A004255
- Coordination sequence for MgZn2, Position Zn1.at n=19A009937
- a(n) = n*(7*n - 1)/2.at n=40A022264
- Number of primitive polynomials of degree n over GF(5).at n=7A027741
- Differences of A038011.at n=26A038012
- Denominators of continued fraction convergents to sqrt(413).at n=7A041785
- Honaker's triangle problem: form a triangle with base of length n, all entries different, all row sums equal; a(n) gives minimal row sum.at n=32A047837
- a(n) = max_{r=1..n-1} ceiling(t(t(n)-t(r-1))/(n-r+1)), where t() = triangular numbers A000217.at n=32A047873
- 12 times triangular numbers.at n=30A049598
- Number of asymmetric mobiles (circular rooted trees) with n nodes and 6 leaves.at n=6A055367
- McKay-Thompson series of class 29A for Monster.at n=29A058611
- Iteration of unitary-sigma function: a(1) = 2, a(n) = usigma(a(n-1)).at n=19A059460
- Numbers k such that sigma(x) = k has exactly 9 solutions.at n=15A060665
- Number of conics which pass through 3 points and are bitangent to a general curve of order n.at n=10A060783
- Non-palindromic number and its reversal are both multiples of 15.at n=39A062914
- Values of m such that N = (am+1)(bm+1)(cm+1) is a 3-Carmichael number (A087788), where a,b,c = 1,2,3.at n=25A064238
- Numbers m such that N = (am+1)(bm+1)(cm+1) is a 3-Carmichael number (A087788), where a,b,c = 1,2,61.at n=0A065698
- Sum of interior angles in an n-sided polygon in degrees.at n=30A066164
- Consider a room of size r X s where rs = 2n and 1 <= r, 1 <= s; count ways to arrange n Tatami mats in room; a(n) = total number of ways for all choices of r and s. Two arrangements are distinguished if one is a rotation or reflection of the other.at n=20A067925
- Smallest multiple of n with a prime signature different from all previous terms.at n=30A069875