13438
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 20160
- Proper Divisor Sum (Aliquot Sum)
- 6722
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 6718
- Möbius Function
- 1
- Radical
- 13438
- 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
- 138
- 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
- yes
- Odd
- no
Appears in sequences
- Sets with a congruence property.at n=16A002703
- a(n) = a(1) + a(2) + ... + a(n-1) + a(m) for n >= 4, where m = 2*n - 2 - 2^(p+1) and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = 1 and a(2) = a(3) = 2.at n=13A049955
- Zero, together with positive numbers k such that prime(k) - k is a square.at n=39A064370
- Number of ways to write the n-th prime as a sum of distinct primes.at n=52A070215
- Triangle in which row n has n semiprimes such that (p+1)(q+1) is the same for each semiprime pq and (p+1)(q+1) is as small as possible.at n=45A180333
- Integers of the form: 0/3 + 1/3 + 2/3 + 3/3 + 5/3 + 7/3 + 11/3 + 13/3 + 17/3 + ....at n=45A182155
- Number of nondecreasing arrangements of n+2 numbers in 0..6 with each number being the sum mod 7 of two others.at n=9A183909
- Monotonic ordering of nonnegative differences 5^i-3^j, for 40>=i>=0, j>=0.at n=26A192150
- Number of nondecreasing -n..n vectors of length 3 whose dot product with some nonincreasing -n..n vector equals 3.at n=21A226400
- Numbers k with property that for every base b >= 2, there is a number m such that m+s(m) = k, where s(m) = sum of digits in the base-b expansion of m.at n=43A230624
- Numbers k such that (14*10^k + 229)/9 is prime.at n=15A294940
- Number of (undirected) Hamiltonian paths on the first n cells of the 7 X ceiling(n/7) knight graph.at n=25A389757