1600
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 7
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 21
- Divisor Sum
- 3937
- Proper Divisor Sum (Aliquot Sum)
- 2337
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 640
- Möbius Function
- 0
- Radical
- 10
- Omega Function (Ω)
- 8
- 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
- yes
- 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
- 29
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- Prime Power
- no
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- yes
- Achilles Number
- no
- Perfect Power
- yes
- Smooth Number
- yes
- Carmichael Number
- no
Classification
- Even
- yes
- Odd
- no
Appears in sequences
- Number of ways of writing n as a sum of 5 squares.at n=28A000132
- Number of ways of writing n as a sum of 5 squares.at n=23A000132
- Restricted permutations.at n=11A000496
- Numbers that are the sum of 2 squares but not sum of 3 nonzero squares.at n=38A000549
- Perfect powers: m^k where m > 0 and k >= 2.at n=50A001597
- Generalized sum of divisors function.at n=31A002132
- Squares and cubes.at n=48A002760
- Discriminants of totally real quartic fields (see comments).at n=2A002769
- a(1) = 3; for n>0, a(n+1) = a(n) + floor((a(n)-1)/2).at n=17A003312
- Numbers of the form 2^i*5^j with i, j >= 0.at n=32A003592
- Numbers k such that 4!*(2k-5)!/(k!*(k-1)!) is an integer.at n=12A004784
- 5!(2n-6)!/n!(n-1)! is an integer.at n=16A004785
- a(n) = (prime(n) - 1)^2.at n=12A005722
- Theta series of D_5 lattice.at n=14A005930
- Number of non-Hamiltonian polyhedra with n nodes.at n=11A007033
- Numbers k such that sigma(x) = k has exactly 3 solutions.at n=44A007372
- Number of strict 3rd-order maximal independent sets in path graph.at n=34A007384
- Shifts 2 places left when e.g.f. is squared.at n=9A007558
- Coordination sequence T2 for Zeolite Code AFY.at n=33A008030
- Coordination sequence T2 for Zeolite Code AST.at n=29A008037