12220
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 7
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 24
- Divisor Sum
- 28224
- Proper Divisor Sum (Aliquot Sum)
- 16004
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 4416
- Möbius Function
- 0
- Radical
- 6110
- Omega Function (Ω)
- 5
- Little Omega Function (ω)
- 4
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
- no
- Narcissistic Number
- no
- Collatz Steps
- 94
- 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
- Expansion of (psi(-x) / phi(-x))^5 in powers of x where phi(), psi() are Ramanujan theta functions.at n=9A001939
- a(n) = n*(n+1)*(n+8)/6.at n=39A006503
- Numbers k for which 10k+1, 10k+3, 10k+7 and 10k+9 are primes.at n=41A007811
- Augmented amicable pairs (smaller member of each pair).at n=1A007992
- Successive positions in Tower of Hanoi (with three pegs {0,1,2}) where xyz means smallest disk is on peg z, second smallest is on peg y, third smallest on peg x, etc. and leading zeros indicate largest disks are all on peg 0.at n=17A055662
- Numbers in base -3.at n=39A073785
- Numbers k such that A003422(k+1)/2 is prime.at n=18A124375
- Sum of squares of four consecutive primes.at n=14A133524
- Nonnegative integers in balanced ternary representation (with 2 standing for -1 digit).at n=42A140267
- A Deutsch-Fibonacci triangle.at n=49A188461
- A Deutsch-Fibonacci triangle.at n=50A188461
- Numbers of rank 11 in the poset of lunar numbers.at n=22A191753
- Number of 0..3 arrays x(0..n-1) of n elements with nondecreasing average value and 0..3 occur with instance counts within one of each other.at n=16A200939
- 9-step Fibonacci sequence starting with 0,1,0,0,0,0,0,0,0.at n=23A251752
- E.g.f.: Limit_{N->oo} [ Sum_{n>=0} (N + n)^(2*n) * (x/N)^n/n! ] / F(x)^N, where F(x) = Limit_{N->oo} [ Sum_{n>=0} (N + n)^(2*n) * (x/N)^n/n! ]^(1/N).at n=4A266522
- Variation on betrothed numbers.at n=2A281265
- Number of permutations of length n sortable by 3 passes through a pop-stack.at n=9A293774
- Even numbers n such that A048633(n+1) = A048633(n).at n=45A331586
- Partial sums of the ziggurat sequence A347186.at n=37A356351
- Ternary numbers consisting of a run of 1's, then a run of 2's, then a run of 0's.at n=9A371051