15195
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 24336
- Proper Divisor Sum (Aliquot Sum)
- 9141
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 8096
- Möbius Function
- -1
- Radical
- 15195
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 133
- 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
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 41.at n=41A031539
- Number of ordered triples (i,j,k) in range [0..n] satisfying i == j mod 2 and j == k mod 3.at n=44A115520
- Numbers k for which 2*k-1, 4*k-1, 8*k-1 and 16*k-1 are primes.at n=20A124494
- Triangle read by rows giving coefficients of Genocchi q-numbers B_n(1,q) (n >= 1) expanded in powers of q.at n=55A193762
- Number of n X 2 0..3 arrays with no element equal to zero plus the sum of elements to its left or zero plus the sum of elements above it or one plus the sum of the elements diagonally to its northwest or one plus the sum of the elements antidiagonally to its northeast, modulo 4.at n=42A239852
- Fixed points of A275957; numbers n for which A060125(n) = A225901(n).at n=36A275843
- Expansion of Product_{k>=0} 1/(1-x^(4*k+1))^(4*k+1).at n=34A285048
- Expansion of Product_{k>=0} 1/(1 + x^(4*k+1))^(4*k+1).at n=34A285287
- Number of partitions of n into 10 or more distinct parts.at n=38A347577