2977
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 25
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 3220
- Proper Divisor Sum (Aliquot Sum)
- 243
- 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
- 2736
- Möbius Function
- 1
- Radical
- 2977
- 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
- 141
- 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
- Expansion of 1/((1-x)^2*(1-x^2)*(1-x^5)*(1-x^10)*(1-x^20)).at n=41A001305
- Hex (or centered hexagonal) numbers: 3*n*(n+1)+1 (crystal ball sequence for hexagonal lattice).at n=31A003215
- Shifts left when inverse Moebius transform applied twice.at n=32A007557
- Coordination sequence T1 for Zeolite Code -ROG.at n=41A009859
- a(n) = floor(n*(n-1)*(n-2)/17).at n=38A011899
- Pseudoprimes to base 18.at n=25A020146
- Pseudoprimes to base 89.at n=38A020217
- Pseudoprimes to base 94.at n=32A020222
- Pseudoprimes to base 95.at n=15A020223
- Strong pseudoprimes to base 18.at n=7A020244
- Strong pseudoprimes to base 89.at n=7A020315
- Strong pseudoprimes to base 94.at n=5A020320
- Strong pseudoprimes to base 95.at n=1A020321
- Numbers k such that the continued fraction for sqrt(k) has period 37.at n=6A020376
- Ordered sequence of distinct terms of the form floor(exp(i) * floor(exp(j))), i,j >= 0.at n=33A022765
- a(n) = Sum{T(i,j)}, 0<=i<=n, 0<=j<=n, T given by A026703.at n=9A026712
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 26 ones.at n=19A031794
- Number of partitions of n such that cn(0,5) = cn(2,5) <= cn(1,5) = cn(3,5) = cn(4,5).at n=64A036855
- Numbers ending with '7' that are the difference of two positive cubes.at n=21A038862
- Number of partitions satisfying cn(0,5) + cn(1,5) + cn(4,5) <= cn(2,5) + cn(3,5).at n=31A039878