11205
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 9
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 20160
- Proper Divisor Sum (Aliquot Sum)
- 8955
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 5904
- Möbius Function
- 0
- Radical
- 1245
- Omega Function (Ω)
- 5
- Little Omega Function (ω)
- 3
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
- yes
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 37
- 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
- no
- Odd
- yes
Appears in sequences
- Numbers k in which the digits of k^2 appear.at n=18A029774
- Numbers k such that k and k^2 have the same set of digits.at n=10A029793
- Numbers whose base-7 representation contains exactly four 4's.at n=20A043412
- Pair the odd numbers such that the k-th pair is (r, r+2k) where r is the smallest odd number not included earlier: (1, 3), (5, 9), (7, 13), (11, 19), (15, 25), (17, 29), (21, 35), (23, 39), (27, 45), ... This is the sequence of the product of the members of pairs.at n=25A075320
- Square array read by antidiagonals: T(n,k) = (k*(2*k+3)^n + 1)/(k+1).at n=33A083075
- Third row of number array A083075.at n=5A083076
- Records in sequence of lengths of suffix blocks associated with A091844.at n=6A091845
- Total number of leaves and roots in the planted trees of order n.at n=11A095339
- a(n) is the number of 3-regular 3-hypergraphs on n labeled vertices. (In a 3-hypergraph, each hyper-edge is a proper 3-set; 3-regular implies that each vertex is in exactly 3 hyperedges.)at n=7A110101
- Numbers k such that k and k^2 use only the digits 0, 1, 2 and 5.at n=47A136822
- Numbers k such that k and k^2 use only the digits 0, 1, 2, 5 and 7.at n=56A136824
- Numbers k such that k and k^2 use only the digits 0, 1, 2, 5 and 8.at n=56A136825
- Number of symmetric matrices with nonnegative integer entries and without zero rows or columns such that sum of all entries is equal to n.at n=8A138178
- Composites that are the sum of two, three, four and five consecutive composite numbers.at n=16A151745
- Numbers with ordered partitions that have periods of length 5.at n=29A178572
- Number of (n+1) X 3 0..2 arrays with no 2 X 2 subblock having the number of clockwise edge increases equal to the number of counterclockwise edge increases in its adjacent leftward or upward neighbors.at n=3A206271
- Number of (n+1) X 5 0..2 arrays with no 2 X 2 subblock having the number of clockwise edge increases equal to the number of counterclockwise edge increases in its adjacent leftward or upward neighbors.at n=1A206273
- T(n,k) = number of (n+1) X (k+1) 0..2 arrays with no 2 X 2 subblock having the number of clockwise edge increases equal to the number of counterclockwise edge increases in its adjacent leftward or upward neighbors.at n=11A206277
- T(n,k) = number of (n+1) X (k+1) 0..2 arrays with no 2 X 2 subblock having the number of clockwise edge increases equal to the number of counterclockwise edge increases in its adjacent leftward or upward neighbors.at n=13A206277
- Deficient numbers n having a companion m > n such that sigma(n)/n = sigma(m)/m.at n=20A212608