5185
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 6696
- Proper Divisor Sum (Aliquot Sum)
- 1511
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 3840
- Möbius Function
- -1
- Radical
- 5185
- 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
- 41
- 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
- Pseudoprimes to base 11.at n=21A020139
- Pseudoprimes to base 13.at n=20A020141
- Pseudoprimes to base 14.at n=20A020142
- Pseudoprimes to base 21.at n=16A020149
- Pseudoprimes to base 29.at n=32A020157
- Pseudoprimes to base 47.at n=39A020175
- Pseudoprimes to base 48.at n=30A020176
- Pseudoprimes to base 62.at n=35A020190
- Pseudoprimes to base 72.at n=24A020200
- Pseudoprimes to base 74.at n=27A020202
- Pseudoprimes to base 82.at n=45A020210
- Pseudoprimes to base 93.at n=38A020221
- Strong pseudoprimes to base 72.at n=9A020298
- Number of singular 2 X 2 matrices over Z(n) (i.e., with determinant = 0).at n=16A020478
- Number of noninvertible 2 X 2 matrices over Z/nZ (determinant is a divisor of 0).at n=15A020479
- a(n) = n*(9*n - 1)/2.at n=34A022266
- a(n) = least m such that if r and s in {1/4, 1/8, 1/12,..., 1/4n} satisfy r < s, then r < k/m < s for some integer k.at n=40A024825
- a(n) = least m such that if r and s in {1/1, 1/2, 1/3, ..., 1/n} satisfy r < s, then r < k/m < (k+3)/m < s for some integer k.at n=37A024843
- Numbers that are the sum of 2 nonzero squares in exactly 4 ways.at n=24A025287
- Numbers that are the sum of 2 nonzero squares in 4 or more ways.at n=24A025295