7380
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
- 22932
- Proper Divisor Sum (Aliquot Sum)
- 15552
- 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
- 1920
- Möbius Function
- 0
- Radical
- 1230
- 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
- 39
- 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
- From random walks on complete directed triangle.at n=17A007829
- Number of ordered triples of integers from [ 2,n ] with no global factor.at n=36A015633
- a(n) = n^4 + n^3 + n^2 + n.at n=9A027445
- 9 times the triangular numbers A000217.at n=40A027468
- Sums of distinct powers of 9.at n=30A033046
- a(n) = 2*n*(4*n + 3).at n=30A033587
- Positive numbers having the same set of digits in base 2 and base 9.at n=26A037414
- Numbers whose maximal base-9 run length is 4.at n=9A037999
- Sums of 4 distinct powers of 9.at n=4A038489
- Numbers having four 1's in base 9.at n=4A043460
- Iterated procedure 'composite k added to sum of its prime factors reaches a prime' yields 7 skipped primes.at n=39A050774
- Number of integers from 1 to 10^n-1 that lack 0 as a digit.at n=4A052386
- Numbers k such that phi(x) = k has exactly 9 solutions.at n=37A060672
- Prime(n^2) +/- n are primes.at n=26A064495
- Sum of interior angles in an n-sided polygon in degrees.at n=40A066164
- Integers y such that for some integer x we have uphi(x) = uphi(y) = x-y, where uphi(n) = A047994(n) is the unitary totient function: If n = Product p_i^e_i, uphi(n) = Product (p_i^e_i - 1).at n=8A067741
- Number of permutations satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..n, with k=1, r=5, I={1,4}.at n=19A079961
- Ordered m for which m = k^3*a*b*(a^4 - b^4) determine (unique) solution triples(k,a,b), where k=1,2,3,... and (a,b) are coprime pairs, not both odd (i.e., of opposite parity).at n=11A081779
- a(n) = (prime(n)+1)*n.at n=41A083726
- a(n) = n*(n+13)*(n+14)/6.at n=27A111144