15185
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
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 18228
- Proper Divisor Sum (Aliquot Sum)
- 3043
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 12144
- Möbius Function
- 1
- Radical
- 15185
- 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
- 177
- 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
- Numbers k such that the continued fraction for sqrt(k) has period 59.at n=23A020398
- Schoenheim bound L_1(n,5,4).at n=33A036832
- Number of nonprimes <= prime(n)^2.at n=31A053683
- Integers m such that the base-10 digit concatenation 2//m//3//m//5//m...//prime(49)//m//prime(50) is prime.at n=33A084048
- Renewal array for 1/(x+sqrt(1-4x)).at n=46A155788
- G.f. satisfies: A(x) = (1 + x*A(x)^3) * (1 + x^2*A(x)).at n=7A200716
- Number of (n+1)X(2+1) 0..1 arrays with the sum of each 2X2 subblock two extreme terms minus its two median terms lexicographically nondecreasing columnwise and nonincreasing rowwise.at n=5A235767
- Number of (n+1)X(6+1) 0..1 arrays with the sum of each 2X2 subblock two extreme terms minus its two median terms lexicographically nondecreasing columnwise and nonincreasing rowwise.at n=1A235771
- T(n,k)=Number of (n+1)X(k+1) 0..1 arrays with the sum of each 2X2 subblock two extreme terms minus its two median terms lexicographically nondecreasing columnwise and nonincreasing rowwise.at n=22A235772
- T(n,k)=Number of (n+1)X(k+1) 0..1 arrays with the sum of each 2X2 subblock two extreme terms minus its two median terms lexicographically nondecreasing columnwise and nonincreasing rowwise.at n=26A235772
- Numbers n for which the digital sum contains the same distinct digits as the digital product but the digital sum is not equal to the digital product.at n=23A249335
- Expansion of 1/sqrt((1 - x^3 - x^5)^2 - 4*x^8).at n=36A376784