6999
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 33
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 5
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 9336
- Proper Divisor Sum (Aliquot Sum)
- 2337
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 4664
- Möbius Function
- 1
- Radical
- 6999
- 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
- 132
- 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
- Smallest k such that the smallest palindrome > k in the Reverse and Add! trajectory of k is reached after exactly n iterations.at n=19A015994
- a(0) = 0. For n > 0, smallest non-palindromic number k such that the smallest palindrome in the Reverse and Add! trajectory of k is reached after exactly n iterations.at n=20A023109
- a(n) = Sum_{j=0..floor(n/2)} T(n,j), T given by A026736.at n=13A026744
- The 5x + 1 sequence beginning at 7.at n=30A028389
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 27.at n=37A031525
- Lucky numbers with size of gaps equal to 14 (upper terms).at n=34A031897
- Least number of Reverse-then-add persistence n.at n=20A033866
- Numbers having three 9's in base 10.at n=6A043527
- Numbers with digits nondecreasing and their reciprocals sum to 1/(positive integer).at n=25A045910
- Smallest number whose sum of digits is n.at n=33A051885
- McKay-Thompson series of class 36C for Monster.at n=38A058646
- Harmonic mean of digits is 8.at n=3A062185
- Smallest composite number with digit sum n.at n=32A067524
- a(n) is the smallest composite number with the sum of digits = the n-th composite number.at n=20A073866
- a(1) = 8; a(n) is smallest number > a(n-1) such that the juxtaposition a(1)a(2)...a(n) is a prime.at n=44A074344
- Numbers n such that A053597(n) sets a new record.at n=10A078515
- Near-repdigit semiprimes with 9 as repeated digit.at n=13A105990
- Semiprimes with semiprime digits (digits 4, 6, 9 only).at n=26A107342
- Starting numbers for which the RATS sequence has eventual period 14.at n=0A114615
- Semiprimes s such that s-/+2 are primes.at n=36A125215