5165
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 17
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 6204
- Proper Divisor Sum (Aliquot Sum)
- 1039
- 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
- 4128
- Möbius Function
- 1
- Radical
- 5165
- Omega Function (Ω)
- 2
- 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
- 54
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- Squarefree Number
- yes
- 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
- Powers of cube root of 13 rounded down.at n=10A018012
- Numbers k such that the continued fraction for sqrt(k) has period 21.at n=28A020360
- Sum of digits in n-th term of A022470.at n=27A022475
- a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = (F(2), F(3), F(4), ...), t = A014306.at n=33A025110
- Gaps of 2 in sequence A038593 (lower terms).at n=9A038643
- Numbers that are divisible by 5 and are the difference between two (different positive) cubes in at least one way.at n=24A038853
- Numbers ending with '5' that are the difference of two positive cubes.at n=17A038860
- a(n) = (n+5)^3 - n^3.at n=16A038867
- Discriminants of real quadratic fields with class number 2 and related continued fraction period length of 5.at n=11A051970
- Numbers k such that 5*2^k + 3 is prime.at n=40A058586
- Smallest integer value > 1 of the form floor((3/2)^k)/floor((3/2)^n).at n=5A065643
- Numbers k such that k*primorial(2473)-1 is prime.at n=36A087832
- Main diagonal of A101858.at n=37A101863
- a(n) = -a(n-2) - a(n-3).at n=42A112455
- Semiprimes a such that there exist three semiprimes b, c and d with a^3=b^3+c^3+d^3.at n=34A113490
- Expansion of e.g.f.: exp(x)*sec(2*x).at n=6A117437
- Composite numbers k such that k+d+1 is prime for all divisors d of k greater than 1.at n=36A120776
- Numbers k such that 2*k+1, 3*k+2 and 4*k+3 are primes.at n=28A126955
- Numbers k such that k and k^2 use only the digits 1, 2, 5, 6 and 7.at n=30A137004
- Numbers k such that continued fraction of (1 + sqrt(k))/2 has period 5.at n=32A146330