15489
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 27
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 22386
- Proper Divisor Sum (Aliquot Sum)
- 6897
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 10320
- Möbius Function
- 0
- Radical
- 5163
- Omega Function (Ω)
- 3
- 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
- 146
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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
- a(n) = T(7,n), array T given by A048471.at n=5A036548
- Sum of the first n primes whose indices are primes.at n=38A083186
- Total number of smallest parts in all partitions of n into odd parts.at n=44A092268
- Triangle, read by rows, such that the binomial transform of the n-th row lists the m-dimensional partitions of n, for n>=1 and m>=0.at n=60A096806
- Retrograde trajectory of 13 under map n -> A132948(n).at n=42A132947
- a(n) = 484*n + 1.at n=31A158326
- a(n) = 32*n^2 + 1.at n=22A158575
- Triangle read by rows: T(n,k) (n >= 1, k >= 0) = number of Dyck paths of semilength k avoiding the pattern U^n D^n.at n=59A238094
- G.f.: Product_{k>=1} (1 + x^k) / (1 - x^(k*(k+1)/2)).at n=33A280422
- a(n) = number of segments (edges) in the configuration A290447(n).at n=22A290866
- Number of nX7 0..1 arrays with every element equal to 0, 1 or 3 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.at n=8A302162