15418
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 24948
- Proper Divisor Sum (Aliquot Sum)
- 9530
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 7104
- Möbius Function
- -1
- Radical
- 15418
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 53
- 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
- yes
- Odd
- no
Appears in sequences
- Shifts left 2 places under COMPOSE transform.at n=11A030277
- Numbers k such that the continued fraction for sqrt(k) has odd period and if the last term of the periodic part is deleted the two central terms are both 14.at n=10A031602
- Number of n X n real (0,1)-matrices with all eigenvalues >= 0.at n=4A086510
- Number of partitions of n such that the set of even parts has only one element.at n=45A090867
- Least k such that k*Mersenne - prime(n) + 1 is prime.at n=27A098556
- a(n) = a(n-1) + 2*a(n-2) + a(n-3) - a(n-4).at n=13A101400
- Irregular triangle read by rows: T(n,k) = number of independent vertex subsets of size k of the graph g_n obtained by attaching two pendant edges to each vertex of the star graph S_n (having n vertices).at n=56A235114
- Number of nX2 0..3 arrays with no three equal values forming an isosceles right triangle, and new values introduced in 0..3 order.at n=4A273961
- T(n,k)=Number of nXk 0..3 arrays with no three equal values forming an isosceles right triangle, and new values introduced in 0..3 order.at n=16A273964
- T(n,k)=Number of nXk 0..3 arrays with no three equal values forming an isosceles right triangle, and new values introduced in 0..3 order.at n=19A273964
- Sum of the largest parts of the partitions of n into 4 parts.at n=45A308760
- Number of reversed integer partitions of 2n whose half-alternating sum is 0.at n=25A357639
- Number of permutations p of [n] satisfying Sum_{i=1..n} (p(i)-i)^2 = 2*n.at n=13A390749