13953
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 18608
- Proper Divisor Sum (Aliquot Sum)
- 4655
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 9300
- Möbius Function
- 1
- Radical
- 13953
- 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
- 133
- 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
- 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 78.at n=37A031576
- Numbers k such that 17^k - 16 is prime.at n=6A034922
- The array in A059216 read by antidiagonals in 'up' direction.at n=40A059217
- The array in A059216 read by antidiagonals in the direction in which it was constructed.at n=40A059234
- Main diagonal of the array A059217.at n=4A059511
- Sum of the first n safe primes.at n=28A066869
- Least integers that satisfy sum(n>0,1/a(n)^z)=0, where a(1)=1, a(n+1)>a(n) and z=I/log(2).at n=9A084817
- Counts compositions as described by table A047969; however, only those ending with an odd part are considered.at n=60A123685
- Number of ways to build a contiguous building with n LEGO blocks of size 1 X 2 on top of a fixed block of the same size so that the building is flat, i.e., with all blocks in parallel position.at n=6A123768
- 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), (0, 1, -1), (1, -1, 1), (1, 0, 0)}.at n=10A148116
- Number of ordered n-tuples of positive integers such that the largest value is n and the first value is odd.at n=5A167633
- Number of singular 2 X 2 matrices having all elements in {-n,...,n}.at n=18A209981
- Number of nX4 0..1 arrays with every element equal to 1, 2 or 4 king-move adjacent elements, with upper left element zero.at n=14A297854
- Product_{n>=1} (1 + x^n)^a(n) = 1 + x + x^2 + 2 * Sum_{n>=3} a(n)*x^n.at n=15A348755
- Numbers k such that k, k + 1, k + 2, and k + 4 are all semiprimes.at n=39A368670