9992
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 29
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 18750
- Proper Divisor Sum (Aliquot Sum)
- 8758
- 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
- 4992
- Möbius Function
- 0
- Radical
- 2498
- Omega Function (Ω)
- 4
- 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
- 179
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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
- Absolute value of Glaisher's alpha(n).at n=27A002290
- If a, b in sequence, so is ab+8.at n=38A009331
- Numbers having three 9's in base 10.at n=29A043527
- a(n) is the largest number which can be formed with no zeros, using least number of digits and having digit sum = n.at n=28A061219
- {Concatenation of n-1 and n+1}/n where n is a member of A069871.at n=6A077192
- Number of positions that are exactly n moves from the starting position in the 2 X 2 X 2 Rubik cube puzzle counting a half-turn as a single move.at n=5A079761
- Numbers k such that k!!!!! - 1 is prime.at n=52A085149
- {a(n)} is monotone increasing, with a(1)=1, a(2)=3 and, for n>2, a(n) is the smallest integer such that a(n) mod a(j) is never a(i) for any pair i,j with 1<=i<j<n.at n=48A100812
- Composite numbers between largest n-digit prime and the smallest (n+1) digit prime.at n=35A109936
- Members of 3-cycles of permutation A111273.at n=8A113701
- Numbers k such that k concatenated with itself gives the product of two numbers which differ by 9.at n=8A116162
- Numbers k such that k * (k+9) is the concatenation of a number m with itself.at n=8A116293
- String of digits encountered in decimal expansion of successive ratios k/(k+1), treating only non-repeating expansions, with decimal point and leading and trailing zeros removed.at n=29A156703
- a(n) = 625*n^2 - 2*n.at n=3A158373
- Number of trisubstituted linear alkanes of composition C_n H_(2n-1) XYZ.at n=13A159941
- Consider the base-5 Kaprekar map n->K(n) defined in A165032. Sequence gives numbers belonging to cycles, including fixed points.at n=10A165037
- Consider the base-5 Kaprekar map n->K(n) defined in A165032. Sequence gives numbers belonging to cycles of length greater than 1.at n=7A165039
- a(n)=10^n-2*n.at n=4A173834
- Number of 4-step one space at a time bishop's tours on an n X n board summed over all starting positions.at n=18A187157
- Monotonic ordering of nonnegative differences 10^i-2^j, for 40>= i>=0, j>=0.at n=32A192125