16519
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 22
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 16520
- Proper Divisor Sum (Aliquot Sum)
- 1
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 16518
- Möbius Function
- -1
- Radical
- 16519
- Omega Function (Ω)
- 1
- Little Omega Function (ω)
- 1
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
- 66
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- yes
- Composite Number
- no
- Semiprime
- no
- Squarefree Number
- yes
- Prime Power
- yes
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 1913
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Numbers k such that (5^k - 1)/4 is prime.at n=14A004061
- Primes of the form m^2 + 3m + 9, where m can be positive or negative.at n=37A005471
- Multiplicity of highest weight (or singular) vectors associated with character chi_183 of Monster module.at n=39A034571
- Numerators of partial sums of reciprocals of lcm(1..n) = A003418(n).at n=11A064857
- Trajectory of n under the Reverse and Add! operation carried out in base 4 (presumably) does not reach a palindrome and (presumably) does not join the trajectory of any term m < n.at n=39A075421
- Primes of the form prime(n)*prime(n*2)+2.at n=5A078622
- a(1) = 1; then primes associated with A091850.at n=34A091851
- Numbers k such that 1 + (x + x^3 + x^5 + x^7 + ... + x^(2*k+1)) is irreducible over GF(2).at n=32A107220
- Primes of the form 55x^2+10xy+199y^2.at n=29A140632
- Primes congruent to 36 mod 53.at n=32A142566
- Primes congruent to 58 mod 59.at n=29A142785
- Primes congruent to 49 mod 61.at n=26A142847
- Least prime number prime(n+k) such that prime(n+k) - prime(k) is a power of 2.at n=48A211674
- Prime sums of five Mersenne primes.at n=38A269666
- Numbers k such that (58*10^k + 221)/9 is prime.at n=20A291661
- Number of prime parts in the partitions of n into 8 parts.at n=42A309437
- Primes p such that 2*p-1 and the concatenation of p and 2*p-1 are primes.at n=44A320445
- Numbers k such that 309*2^k+1 is prime.at n=29A323144
- Expansion of Product_{i>=1, j>=0} (1 + x^(i * 3^j)).at n=46A327726
- Matula-Goebel numbers of rooted trees whose number of nodes is one more than their node-height.at n=31A358731