16831
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
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 16832
- 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
- 16830
- Möbius Function
- -1
- Radical
- 16831
- 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
- 110
- 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
- yes
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 1943
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Let A(n) = #{(i,j,k): i^2 + j^2 + k^2 <= n}, V(n) = (4/3)*Pi*n^(3/2), P(n) = A(n) - V(n); A000092 gives values of n where |P(n)| sets a new record; sequence gives A(A000092(n)).at n=16A000413
- Number of nodes in regular n-gon with all diagonals drawn.at n=29A007569
- Primes that are palindromic in base 11.at n=26A029978
- Number of asymmetric Greg trees.at n=14A052303
- First member of a prime quadruple in a p^2+p-1 progression.at n=6A057325
- Centered 17-gonal numbers: (17*n^2 - 17*n + 2)/2.at n=44A069130
- Total number of parts in all partitions of n into relatively prime parts.at n=24A085410
- Primes whose digit reversal is a triangular number.at n=10A115705
- Mother primes of order 8.at n=29A136067
- Primes of the form 55x^2+10xy+199y^2.at n=30A140632
- Primes of the form 210k + 31.at n=37A140846
- Primes congruent to 30 mod 53.at n=39A142560
- Primes congruent to 16 mod 59.at n=31A142743
- Primes congruent to 56 mod 61.at n=33A142854
- a(n) = number of n-digit numbers not divisible by any of their digits.at n=4A147963
- (Partial sums of the squarefree integers) that are prime.at n=9A194128
- Primes p such that 2p^2-1, 3p^2-2 and 4p^2-3 are also prime.at n=7A213079
- Primes whose base-7 representation also is the base-4 representation of a prime.at n=43A235617
- Primes p such that p - 2 and p^3 - 2 are also prime.at n=37A240126
- Centered 17-gonal (or heptadecagonal) primes.at n=8A264824