12287
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 13416
- Proper Divisor Sum (Aliquot Sum)
- 1129
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 11160
- Möbius Function
- 1
- Radical
- 12287
- 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
- 156
- 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
- A nonlinear recurrence.at n=39A003073
- Composite numbers whose prime factors contain no digits other than 1 and 7.at n=32A036307
- Numbers whose maximal base-8 run length is 4.at n=34A037995
- Numbers having four 7's in base 8.at n=2A043452
- a(0) = 1; a(n) = 3*2^n - 1, for n > 0.at n=12A052940
- a(2n) = 2*2^n - 1, a(2n+1) = 3*2^n - 1.at n=25A052955
- Consider all integer triples (i,j,k), j,k>0, with binomial(i+2,3)=binomial(j+2,3)+k^3, ordered by increasing i; sequence gives i values.at n=39A054221
- A054221 without cubes.at n=17A054224
- a(0) = 0; for n > 0, a(n) = 3*2^(n-1) - 1.at n=13A055010
- Duplicate of A055010.at n=13A060153
- a(n) = 48*n^2 - 1.at n=16A065532
- Smallest number m so that n^2 + A000330(m) is also a square, i.e., n^2 + (1 + 4 + 9 + 16 + ... + m^2) = w^2 for some w.at n=16A065610
- Nonprime solutions to k == -1 (mod phi(k+1)).at n=35A067930
- Numbers m such that the minimal value of abs(2^m - 3^x) > 0 is prime (i.e., m such that A064024(m) is prime).at n=26A073073
- a(1) = 2, a(n+1) = smallest squarefree number == 1 (mod a(n)) and > a(n).at n=13A076698
- Duplicate of A076698.at n=13A076993
- Variation on Ulam numbers: a(1) = 1; a(2) = 2; for n>2, a(n) = smallest (n odd) or largest (n even) number > a(n-1) that is a unique sum of two distinct earlier terms.at n=25A081026
- a(0) = 1; for n > 0, a(n) = 3*2^(n-1) - 1.at n=13A083329
- Add 1, double, add 1, double, etc.at n=25A083416
- Duplicate of A055010.at n=13A086219