13273
domain: N
Properties
Digital Properties
- Digit Count
- 5
- 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
- 14308
- Proper Divisor Sum (Aliquot Sum)
- 1035
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 12240
- Möbius Function
- 1
- Radical
- 13273
- 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
- 94
- 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
- Number of squares on infinite chessboard at <= n knight's moves from a fixed square.at n=31A018836
- Numbers k such that the continued fraction for sqrt(k) has odd period and if the last term of the periodic part is deleted then there are a pair of central terms both equal to 8.at n=27A031421
- a(n) = floor((4/3)^n).at n=33A064628
- Values of floor((4/3)^n) that are composite.at n=22A070761
- Composite n such that both n and its reversal in base 10 are squarefree, none of the prime factors of n are palindromes and the prime factors of the reversal of n are the reversals of those of n.at n=2A083526
- a(n) = n*(n^3-n^2+n+1)/2.at n=13A100855
- The sum of the next n terms of A114103.at n=12A114105
- Number of ordered triples (i,j,k) in range [0..n] satisfying i == j mod 2 and j == k mod 3.at n=42A115520
- Integers of the form (x^3)/6 + (x^2)/2 + x + 1.at n=14A127876
- a(n) = n^3 - 3*(n+3)^2.at n=25A153260
- a(n) = n^3 - 4*n^2 + 6*n - 2.at n=22A188377
- T(n,k)=Number of nXk 0..3 arrays with no element equal to one plus the sum of elements to its left or zero plus the sum of the elements above it or zero plus the sum of the elements diagonally to its northwest or one plus the sum of the elements antidiagonally to its northeast, modulo 4.at n=60A241054
- Number of partitions p of n such that (number of numbers in p that have multiplicity 1) = (number of numbers in p having multiplicity > 1).at n=44A241274
- Numbers missing from A001032 despite satisfying the necessary congruence conditions (see comments).at n=31A274469
- Nearest integer to (4/3)^n.at n=33A309212
- Number of ways to split a strict composition of n into contiguous subsequences all having the same sum.at n=26A336130
- G.f. satisfies A(x) = exp( Sum_{k>=1} (2 * (-1)^k + A(x^k)) * x^k/k ).at n=45A363565
- a(0) = 1; for n > 0, a(n) is the coefficient of x^a(n-1) in the expansion of Product_{k=0..n-1} (x^a(k) + 1 + 1/x^a(k)).at n=18A367736
- Natural numbers repeated 3 times are taken in parts of successive lengths 1,2,3,..., and a(n) is the sum of the numbers in the part with length n.at n=42A370880
- Number of integer compositions of n whose leaders of anti-runs are identical.at n=16A374517