2755
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 3600
- Proper Divisor Sum (Aliquot Sum)
- 845
- 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
- 2016
- Möbius Function
- -1
- Radical
- 2755
- 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
- yes
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 159
- 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
- no
- Odd
- yes
Appears in sequences
- Number of n-step mappings with 4 inputs.at n=10A005945
- Coordination sequence T4 for Zeolite Code CON.at n=37A009871
- Coordination sequence T4 for Zeolite Code DFO.at n=40A009878
- a(n) = floor( n*(n-1)*(n-2)/25 ).at n=42A011907
- Pseudoprimes to base 59.at n=20A020187
- Pseudoprimes to base 86.at n=23A020214
- Index of 5^n within sequence of numbers of form 2^i * 5^j.at n=48A022334
- a(1) = 3; a(n+1) = a(n)-th composite.at n=23A022451
- Number of 9's in all partitions of n.at n=34A024793
- a(n) = sum of the numbers between the two n's in A026346.at n=34A026349
- a(n) = least k such that 1+2+...+k >= E{1,2,...,n}, where E is the 3rd elementary symmetric function.at n=21A027917
- An "extremely strange sequence": a(n+1) = [ A*a(n)+B ]/p^r, where p^r is the highest power of p dividing [ A*a(n)+B ] and p=2, A=4.001, B=1.2.at n=37A028948
- Lucky numbers with size of gaps equal to 8 (lower terms).at n=30A031890
- Composite numbers k, not a power of 2, such that the E(k) == 1 (mod k), where E(k) is the k-th Euler number (A000364).at n=18A035163
- Coordination sequence Z12 for Zeolite Code STT.at n=35A038416
- Number of partitions satisfying cn(0,5) + cn(1,5) < cn(2,5) + cn(3,5) and cn(0,5) + cn(4,5) < cn(2,5) + cn(3,5).at n=31A039884
- Smallest k>1 such that k(p-1)-1 is divisible by p^2, p=n-th prime.at n=15A039914
- Denominators of continued fraction convergents to sqrt(75).at n=9A041133
- The sequence e when b=[ 1,1,1,1,0,1,1,1,... ].at n=58A042959
- Numbers k such that string 0,1 occurs in the base 9 representation of k but not of k-1.at n=36A044252