2257
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 16
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 2356
- Proper Divisor Sum (Aliquot Sum)
- 99
- 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
- 2160
- Möbius Function
- 1
- Radical
- 2257
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 37
- 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
- no
- Odd
- yes
Appears in sequences
- Number of sublattices of index n in generic 3-dimensional lattice.at n=46A001001
- Numbers k such that phi(2k+1) < phi(2k).at n=29A001837
- Central polygonal numbers: a(n) = n^2 - n + 1.at n=48A002061
- a(1) = 0, a(2) = -2; for n > 2, a(n) + a(n-2) - a(n-3) - a(n-5) - ... - a(n-p) = (-1)^(n+1)*n if n is prime, otherwise = 0, where p = largest prime < n.at n=47A002120
- Numbers that are the sum of 10 positive 6th powers.at n=31A003366
- Coordination sequence T3 for Zeolite Code EMT.at n=39A008088
- Expansion of (1+x^5)/((1-x)*(1-x^2)*(1-x^3)*(1-x^4)).at n=52A008766
- Coordination sequence T2 for Zeolite Code VSV.at n=30A009915
- a(1)=1, a(n) = n*8^(n-1) + a(n-1).at n=3A014921
- Pseudoprimes to base 11.at n=15A020139
- Pseudoprimes to base 14.at n=14A020142
- Pseudoprimes to base 29.at n=24A020157
- Pseudoprimes to base 47.at n=29A020175
- Pseudoprimes to base 48.at n=18A020176
- Pseudoprimes to base 60.at n=8A020188
- Pseudoprimes to base 75.at n=20A020203
- Pseudoprimes to base 82.at n=34A020210
- Strong pseudoprimes to base 29.at n=5A020255
- Strong pseudoprimes to base 47.at n=8A020273
- Strong pseudoprimes to base 48.at n=7A020274