5491
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 6140
- Proper Divisor Sum (Aliquot Sum)
- 649
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 4896
- Möbius Function
- 0
- Radical
- 323
- Omega Function (Ω)
- 3
- 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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 41
- 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 k^4 can be written as a sum of four positive 4th powers.at n=36A003294
- Expansion of x*(1+x-x^2)/((1-x)^4*(1+x)).at n=38A005744
- a(n) = (2*n - 15)*n^2.at n=17A015247
- a(n) = 2*(n+1) + 3*n + ... + (k+1)*(n+2-k), where k = floor((n+1)/2).at n=36A024305
- a(n) = least m such that if r and s in {1/1, 1/3, 1/5, ..., 1/(2n-1)} satisfy r < s, then r < k/m < (k+2)/m < s for some integer k.at n=32A024841
- Sorted k-factorial numbers (numbers of form k-1 excluded).at n=21A028687
- Sorted factorial and k-factorial numbers (numbers of form k-1 excluded).at n=27A028688
- Number of ways to partition n elements into pie slices of different sizes.at n=29A032153
- Products p^3 or p^2*q, where {p,q} are consecutive primes.at n=19A033477
- Numbers k such that k^4 can be written as a sum of four positive 4th powers with no common factor.at n=13A039664
- Numbers with a sum of digits equal to their greatest prime factor.at n=37A052021
- Numbers k such that 3*2^k + 7 is prime.at n=27A059746
- a(n) = (n^3 + 5*n + 18)/6.at n=34A060163
- Composite numbers not divisible by 2, 3 or 5 which contain their largest prime factor as a substring in base 2.at n=39A063137
- Numbers k such that phi(P(k)) - P(phi(k)) = 1, where P(k) is the largest prime factor of k.at n=42A070002
- Numbers k such that (sigma(k)-k) - Sum_{p|k} p^2 = -1.at n=4A070225
- Numbers n such that sum of digits of n equals the squarefree part of n.at n=39A070274
- a(1) = 4; a(n) = average of the largest and the smallest n-digit primes.at n=3A073863
- Numbers n such that n#*2^n+1 is prime, where n# = product of primes <= n.at n=45A084404
- Binomial transform of A084624.at n=9A084625