15095
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 18120
- Proper Divisor Sum (Aliquot Sum)
- 3025
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 12072
- Möbius Function
- 1
- Radical
- 15095
- 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
- 115
- 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
- Expansion of Product_{m>=1} (1+x^m)^5.at n=12A022570
- T(n, 2*n-3), T given by A027960.at n=42A027965
- Fibonacci iteration starting with (1, a(n)) leads to a "nine digits anagram".at n=21A034587
- a(n) = (n^3 + 6n^2 - n + 12)/6.at n=43A074742
- Number of sets of distinct primes, the greatest of which is prime(n), whose arithmetic mean is an integer.at n=17A082552
- Numbers k such that (67*10^(k-1) + 23)/9 is a depression prime.at n=8A082712
- Diagonal of array A085205.at n=12A085228
- Numbers that reach the fixed point 89 under iteration of f(x) = reverse(x) - maxdigit(x).at n=22A097155
- Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1000-1111-0001 pattern in any orientation.at n=17A146606
- Numbers n such that A277118(n) = 15.at n=3A277512
- Subword complexity of the infinite word Product_{i>=1} Product_{j=1..i} a^(i-j+1) b^j.at n=44A338760
- a(1) = a(2) = 1; a(n) = gcd(a(n-1), a(n-2)) + (a(n-1) + a(n-2))/gcd(a(n-1), a(n-2)).at n=23A355898
- a(n) = 8*n^2 - 9*n + 3.at n=44A360416