13981
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
- 3
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 16128
- Proper Divisor Sum (Aliquot Sum)
- 2147
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 12000
- Möbius Function
- -1
- Radical
- 13981
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 58
- 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
- Deceptive nonprimes: composite numbers k that divide the repunit R_{k-1}.at n=23A000864
- Fermat pseudoprimes to base 2, also called Sarrus numbers or Poulet numbers.at n=28A001567
- Divisors of 2^20 - 1.at n=37A003529
- Pseudoprimes to base 5.at n=25A005936
- Pseudoprimes to base 10.at n=38A005939
- Number of symmetric plane partitions of n.at n=36A005987
- sin(cos(x)*arcsin(x))=x-3/3!*x^3+25/5!*x^5-371/7!*x^7+11985/9!*x^9...at n=5A012481
- Expansion of 1/((1-5*x)*(1-9*x)).at n=4A016163
- Pseudoprimes to base 20.at n=37A020148
- Pseudoprimes to base 21.at n=29A020149
- Pseudoprimes to base 39.at n=29A020167
- Pseudoprimes to base 40.at n=41A020168
- Pseudoprimes to base 42.at n=32A020170
- Pseudoprimes to base 72.at n=35A020200
- Pseudoprimes to base 78.at n=32A020206
- Pseudoprimes to base 84.at n=31A020212
- Pseudoprimes to base 90.at n=25A020218
- Strong pseudoprimes to base 59.at n=18A020285
- Strong pseudoprimes to base 78.at n=15A020304
- Strong pseudoprimes to base 100.at n=25A020326