9818
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 26
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 14730
- Proper Divisor Sum (Aliquot Sum)
- 4912
- 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
- 4908
- Möbius Function
- 1
- Radical
- 9818
- 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
- 135
- 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
- yes
- Odd
- no
Appears in sequences
- Numbers k such that the continued fraction for sqrt(k) has period 33.at n=25A020372
- Numbers whose base-4 representation contains exactly three 1's and four 2's.at n=19A045104
- Sum of next n even interprimes.at n=12A075675
- Sum of composite numbers less than n-th prime.at n=36A079725
- a(n) = (Sum_{k=1..n} A073698(k))^(1/n).at n=44A093928
- Numbers k such that (10^(2*k+1)+18*10^k-1)/9 is prime.at n=5A107123
- The largest part summed over all partitions of n in which every integer from the smallest part to the largest part occurs.at n=42A117469
- Smallest m such that (sum of binary digits of m*(m+1)/2) = n.at n=22A211201
- Numbers n such that n^2 + 1 is divisible by a 4th power.at n=32A218563
- Number of simple connected graphs with n nodes that are triangle-free and not integral.at n=9A243326
- Numbers k such that (2*10^k - 71)/3 is prime.at n=21A280449
- Number of free pure symmetric multifunctions with leaves a multiset whose multiplicities are the integer partition with Heinz number n.at n=32A317655
- Number of n-regular, N_0-weighted pseudographs on 2 vertices with total edge weight 9, up to isomorphism.at n=30A358249
- Even integers x such that x + sqrt(y) = sqrt(x || y), where || denotes decimal concatenation and y is a perfect square.at n=39A390123
- Upper (3/2)-midsequence of binomial(n,3) and binomial(n,2); see Comments.at n=34A390343