16019
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 17
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 16296
- Proper Divisor Sum (Aliquot Sum)
- 277
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 15744
- Möbius Function
- 1
- Radical
- 16019
- 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
- 45
- 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
- "AGK" (ordered, elements, unlabeled) transform of 1,2,3,4...at n=12A032025
- Number of directed cycles of B-trees of order 3 with n labeled leaves.at n=17A058519
- Main diagonal of array in A083140.at n=22A083141
- Indices of primes in the sequence defined by A(0) = 31, A(n) = 10*A(n-1) + 71 for n > 0.at n=18A101844
- Number of solutions to +-p(1)+-p(2)+-...+-p(2n) = 3 where p(i) is the i-th prime.at n=10A113042
- Numerator of Sum/Product of first n Lucas numbers A000032[n].at n=20A121709
- Cyclops numbers whose squares are cyclops numbers.at n=22A239827
- (p^2 - 3)/2 for odd primes p.at n=39A243887
- Number of partitions of 5n into 5 parts.at n=16A256225
- Number of partitions of 2n into exactly 5 parts.at n=40A256309
- Number of partitions of 4n into exactly 5 parts.at n=20A256316
- Number of partitions of 3n into at most 5 parts.at n=25A256525
- Number of partitions of 3*n^2 into parts that are at most n.at n=5A258293
- Numbers n such that the concatenation of the first n digits of the digital expansion of 1/137 is prime.at n=6A264725
- Numbers that cannot be written as a difference of 11-smooth numbers.at n=27A326319
- Nonprime numbers k for which k*k' is a palindrome, where k' is the arithmetic derivative of k (A003415).at n=15A359331
- a(n) = floor(Product_{k=1..n} log(prime(k))).at n=11A360569
- G.f. A(x) satisfies A(x) = 1 / ((1 - x) * (1 - x * (1 + x) * A(x^2))).at n=12A367713