5155
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 16
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 6192
- Proper Divisor Sum (Aliquot Sum)
- 1037
- 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
- 4120
- Möbius Function
- 1
- Radical
- 5155
- 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
- 28
- 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
- Cycle class sequence c(2n) (the number of true cycles of length 2n in which a certain node is included) for zeolite DFO = DAF-1 [Mg14Al52P66O264].7R.40H2O starting with a T6 atom.at n=5A019006
- Every prefix prime in base 6 (written in base 6).at n=21A024766
- Number of partitions of n into distinct parts >= 2.at n=59A025147
- Sequence satisfies T^2(a)=a, where T is defined below.at n=49A027594
- Numbers having three 5's in base 10.at n=6A043511
- Number of 4 X 4 symmetric stochastic matrices under row and column permutations.at n=16A052281
- Numbers with all odd digits, in which each digit divides the number formed by the rest, i.e., the number obtained by just removing this digit.at n=32A061507
- Table M(n,b) (columns: n >= 1, rows: b >= 0) gives the number of site swap juggling patterns with exact period n, using exactly b balls, where cyclic shifts are not counted as distinct.at n=60A065177
- a(n) = Sum_{0 < d <= t <= n, d|n, t|n} d*t.at n=39A067692
- Near-repdigit semiprimes with 5 as repeated digit.at n=16A105986
- Number of triples (p,q,r) of primes with p<q<r<=prime(n), p+q>r, q+r>p and r+p>q.at n=44A138226
- Triangle read by rows: T(n,k) = 1 + n! - k! - (n - k)! + k!*(n - k)!.at n=31A155453
- Triangle read by rows: T(n,k) = 1 + n! - k! - (n - k)! + k!*(n - k)!.at n=32A155453
- Lesser of twin primes, written in base 6.at n=40A166479
- A175366(n^2).at n=30A175367
- a(n) = A057641(A094348(n)).at n=24A181852
- Triangular array read by rows: T(n,k) is the number of partial permutations of {1,2,...,n} that have exactly k cycles, 0<=k<=n.at n=22A216294
- Conjectured lower bounds for the Riemann hypothesis function floor(H(k) + exp(H(k))*log(H(k))) - sigma(k).at n=14A222761
- Number of lattice points in the closed region bounded by the graphs of y = (5/6)*x^2, x = n, and y = 0, excluding points on the x-axis.at n=25A227347
- Composite squarefree numbers n such that p + tau(n) divides n - phi(n), where p are the prime factors of n, tau(n) = A000005(n) and phi(n) = A000010(n).at n=28A229324