11172
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 12
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 36
- Divisor Sum
- 31920
- Proper Divisor Sum (Aliquot Sum)
- 20748
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 3024
- Möbius Function
- 0
- Radical
- 798
- Omega Function (Ω)
- 6
- 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
- no
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 112
- 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
- Number of partitions into one kind of 1's, two kinds of 2's, and three kinds of 3's.at n=36A002597
- a(n) = Sum_{i=1..floor((n+1)/4)} a(2*i-1) * a(n-2*i+1), with a(1)=a(2)=1.at n=24A024722
- 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 70.at n=31A031568
- Numbers divisible by the sum and product of their digits.at n=47A038186
- Expansion of (1+2*x+3*x^2)/((1-x)^3*(1-x^2)).at n=27A055232
- Numbers k such that sigma(x) = k has exactly 10 solutions.at n=15A060666
- Numbers k such that iterating phi(sigma(k)-phi(k)) starting from k leads to the fixed point 8064.at n=10A077096
- Smallest k such that k*Mersenne_prime(n)^2 -1 (or k*A000668(n)^2 -1) is prime.at n=21A098818
- Triangular matrix T, read by rows, that satisfies: T^2 + T = SHIFTUP(T), also T^(n+1) + T^n = SHIFTUP(T^n - D*T^(n-1)) for all n, where D is a diagonal matrix with diagonal(D) = diagonal(T) = {1,2,3,...}.at n=41A103238
- Dividuus numbers: numbers which are divisible by (1) the sum of their digits,(2) the product of their digits,(3) the digital root and (4) the multiplicative digital root.at n=37A118575
- Numbers k such that the set of prime factors of phi(k) is a proper subset of the set of prime factors of k and the set of prime factors of k is a proper subset of the set of prime factors of sigma(k).at n=32A141717
- Averages of twin prime pairs of A154546.at n=40A154548
- Row sums of triangle defined in A113820.at n=32A160968
- Number of nondecreasing arrangements of n numbers in -3..3 with sum zero and sum of squares not greater than n*12/3.at n=25A183921
- Numbers k such that sopfr(k + bigomega(k)) = sopfr(k).at n=24A187877
- Triangle read by rows: Bell polynomial of the second kind B(n,k) with argument vector (7, 42, 210, 840, 2520, 5040, 5040).at n=7A188066
- a(n) = 7*n*(2*n + 1).at n=28A195026
- Numbers k for which sigma(k)/k - 6/7 is an integer.at n=1A218413
- Numbers k such that the product of divisors of sigma(k) is divisible by the product of divisors of k.at n=19A219362
- Numbers divisible by the square of each digit.at n=44A225299