13972
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 22
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 5
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 28000
- Proper Divisor Sum (Aliquot Sum)
- 14028
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- yes
Derived Values
- Euler's Totient
- 5976
- Möbius Function
- 0
- Radical
- 6986
- Omega Function (Ω)
- 4
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 151
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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
- a(n) = Sum_{i=0..n} A047130(i, n-i).at n=15A047131
- Let (u1,u2) be successive untouchable numbers such that phi(u1) = phi(u2); sequence gives values of u2.at n=30A048190
- Twice the positions in A051686 at which new primes appear in that sequence.at n=40A051861
- Constant term in the reduction by (x^2->x+1) of the polynomial p(n,x) defined below at Comments.at n=11A192921
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 838", based on the 5-celled von Neumann neighborhood.at n=39A273681
- Floor of area of triangle whose sides are consecutive Ulam numbers (A002858).at n=36A330909
- Numbers that are the sum of eight fourth powers in seven or more ways.at n=21A345582
- Numbers that are the sum of eight fourth powers in exactly seven ways.at n=20A345839