5271
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 15
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 8064
- Proper Divisor Sum (Aliquot Sum)
- 2793
- 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
- 3000
- Möbius Function
- -1
- Radical
- 5271
- Omega Function (Ω)
- 3
- Little Omega Function (ω)
- 3
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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 54
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- 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
- Numbers that are the sum of 10 positive 7th powers.at n=28A003377
- Pseudoprimes to base 20.at n=22A020148
- Number of 3's in n-th term of A007651.at n=36A022468
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 23.at n=28A031521
- Numbers k such that k | 11^k + 10^k + 9^k + 8^k + 7^k + 6^k + 5^k + 4^k + 3^k.at n=28A057286
- Numbers n such that phi((prime(n)+1)/2)=sigma(n).at n=23A068473
- Composites which use more than all their digits in their prime factorization.at n=43A074237
- a(1) = 4 and then least composite such that every partial concatenation of 2 or more terms is a prime.at n=38A086474
- Numbers n such that 4*10^n + 8*R_n - 5 is prime, where R_n = 11...1 is the repunit (A002275) of length n.at n=13A102998
- Indices of Fibonacci numbers in A073656, i.e., A073656(n) = F(a(n)).at n=12A119755
- Poincaré series [or Poincare series] P(C#_{3,2}; x).at n=22A124630
- Number of symmetric bushes with n edges. I.e., number of ordered trees with n edges, no non-root vertices of outdegree 1 and symmetrical with respect to the vertical axis passing through the root.at n=21A125189
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 1), (-1, 0, 1), (1, -1, 1), (1, 0, -1), (1, 1, 1)}.at n=7A149718
- Values of k arising in A160518: numbers k such that (2*k^3 - 1, 2*k^3 + 1) are twin primes.at n=45A151612
- Triangle defined by T(n,k) = T(n-1,k-1) + Sum_{j=k..n-2} T(n-1,j)*2^j*T(j,k-1) for n>k>0 with T(n,n)=T(n,0)=1, read by rows.at n=41A152795
- Integers of the form m*(6*m -+ 1)/2.at n=40A154292
- a(n) = 2*n^2 + 18*n + 7.at n=46A154591
- Numbers of the form p*q*r, where p < q < r are odd primes such that r = +/-1 (mod p*q).at n=28A160353
- Integer averages of the set of the first positive squares up to some n^2.at n=41A164576
- a(n) = 5*n^2 + 5*n - 9.at n=31A166150