15203
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 11
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 15888
- Proper Divisor Sum (Aliquot Sum)
- 685
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 14520
- Möbius Function
- 1
- Radical
- 15203
- 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
- 32
- 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
- Centered dodecahedral numbers.at n=11A005904
- Pseudoprimes to base 3.at n=27A005935
- Strong pseudoprimes to base 9.at n=19A020235
- Strong pseudoprimes to base 81.at n=26A020307
- For smallest numbers k such that A082596(k) = n, sequence gives A060863(k).at n=3A082653
- Partial sums of A084263.at n=44A084570
- Number of sets of points determined by the intersection of a line with an n X n grid of points.at n=16A119438
- Nonprimes k such that 3^k == 3 (mod k).at n=35A122780
- Row sums of inverse of number triangle A(n,k) = 1/L(n+1) if k <= n <= 2k, 0 otherwise, where L(n) = A000032(n).at n=21A127754
- a(1)=1, a(n)=a(n-1)+n^0 if n odd, a(n)=a(n-1)+ n^2 if n is even.at n=44A135301
- Column 2 of triangle A152798; first differences of A122889.at n=10A152799
- Terms of A122780 which are not Carmichael numbers A002997.at n=27A153514
- Numbers k such that the digit sum of 167^k is divisible by k.at n=30A175552
- Number of 4-bead necklaces labeled with numbers -n..n not allowing reversal, with sum zero.at n=21A208598
- Euler pseudoprimes to base 9: composite integers such that abs(9^((n - 1)/2)) == 1 mod n.at n=34A263239
- Expansion of Product_{k>=1} 1/((1 - x^k) * (1 - x^(2*k)) * (1 - x^(3*k)) * (1 - x^(4*k)) * (1 - x^(5*k))).at n=21A327044
- Super pseudoprimes (or superpseudoprimes) to base 3: Fermat pseudoprimes to base 3 all of whose divisors that are larger than 1 are either primes or Fermat pseudoprimes to base 3.at n=13A328662
- Numbers that are sums of consecutive centered dodecahedral numbers (A005904).at n=43A329658
- Odd pseudoprimes to base 3; composite terms of A271116.at n=26A351336