1842
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 15
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 3696
- Proper Divisor Sum (Aliquot Sum)
- 1854
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- yes
Derived Values
- Euler's Totient
- 612
- Möbius Function
- -1
- Radical
- 1842
- Omega Function (Ω)
- 3
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 130
- Smith Number
- yes
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- 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
- Number of unlabeled rooted trees with n nodes (or connected functions with a fixed point).at n=11A000081
- Numbers that are the sum of 8 positive 6th powers.at n=23A003364
- Cascade-realizable Boolean functions of n variables.at n=4A005613
- Coordination sequence T3 for Zeolite Code VET.at n=26A009904
- Coordination sequence T4 for Zeolite Code VET.at n=26A009905
- a(n) = floor(n*(n-1)*(n-2)*(n-3)/31).at n=17A011941
- Numbers k that divide s(k), where s(1)=1, s(j)=18*s(j-1)+j.at n=36A014868
- Expansion of 1/Product_{m>=1} (1 - m*q^m)^18.at n=3A022742
- Numbers k such that Fibonacci(k) == -8 (mod k).at n=24A023166
- Convolution of natural numbers >= 2 and Lucas numbers.at n=10A023549
- a(n) = [ Sum{(sqrt(j+1)-sqrt(i+1))^2} ], 1 <= i < j <= n.at n=32A025222
- a(n) = n^2 - 7.at n=40A028881
- 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 42.at n=7A031540
- Numbers with the property that all pairs of consecutive base-4 digits differ by more than 1.at n=45A032967
- Rooted tree triangle read by rows: a(n,k) = number of forests with n nodes and k rooted trees.at n=55A033185
- Number of partitions of n into parts not of form 4k+2, 20k, 20k+7 or 20k-7. Also number of partitions in which no odd part is repeated, with at most 3 parts of size less than or equal to 2 and where differences between parts at distance 4 are greater than 1 when the smallest part is odd and greater than 2 when the smallest part is even.at n=36A036027
- Digit sum of composite even number equals digit sum of juxtaposition of its prime factors (counted with multiplicity).at n=39A036924
- Inverse WEIGH transform of A038000.at n=41A038001
- Inverse WEIGH transform of A038000.at n=20A038001
- Number of partitions satisfying cn(0,5) + cn(1,5) + cn(4,5) <= 1.at n=42A039852