1898
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
- 8
- Divisor Sum
- 3108
- Proper Divisor Sum (Aliquot Sum)
- 1210
- 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
- 864
- Möbius Function
- -1
- Radical
- 1898
- 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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 37
- Smith Number
- no
- 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
- Coefficient of q^(2n-1) in the series expansion of Ramanujan's mock theta function f(q).at n=32A000199
- Number of partitions of n into at most 5 parts.at n=41A001401
- a(n) = Sum_{d|n, d == 1 mod 4} d^2 - Sum_{d|n, d == 3 mod 4} d^2.at n=44A002173
- Smallest multiple of n whose digits sum to n.at n=26A002998
- Expansion of x*(1+x-x^2)/((1-x)^4*(1+x)).at n=26A005744
- Prime(n)*...*prime(a(n)) is the least product of consecutive primes that is non-deficient.at n=29A007684
- Prime(n)*...*prime(a(n)) is the least product of consecutive primes which is abundant.at n=29A007707
- Number of factors in the infinite word formed by the Kolakoski sequence A000002.at n=46A007782
- Coordination sequence T3 for Zeolite Code FER.at n=27A008108
- Coordination sequence T1 for Zeolite Code LAU.at n=31A008124
- Coordination sequence T2 for Milarite.at n=27A008257
- Numbers k such that the continued fraction for sqrt(k) has period 7.at n=17A010338
- Coefficients in expansion of Pi as Sum_{n>=1} a(n)/(n*n!*(n+1)!), as found by greedy algorithm.at n=53A011191
- Seven iterations of Reverse and Add are needed to reach a palindrome.at n=24A015986
- Pisot sequence L(5,8).at n=11A020736
- Number of 3's in n-th term of A006711.at n=32A022479
- a(n) = [ a(n-1)/a(1) ] + [ a(n-2)/a(2) ] + ... + [ a(1)/a(n-1) ], for n >= 3.at n=17A022864
- a(n) = 2*(n+1) + 3*n + ... + (k+1)*(n+2-k), where k = floor((n+1)/2).at n=24A024305
- a(n) = Sum_{i=1..floor((n+2)/4)} a(2i-1)*a(n-2i+1), with a(1)=3, a(2)=1, and a(3)=2.at n=8A024963
- a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = (composite numbers), t = (odd natural numbers).at n=15A025104