7100
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 8
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 18
- Divisor Sum
- 15624
- Proper Divisor Sum (Aliquot Sum)
- 8524
- 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
- 2800
- Möbius Function
- 0
- Radical
- 710
- Omega Function (Ω)
- 5
- 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
- no
- Narcissistic Number
- no
- Collatz Steps
- 88
- 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
- no
- Achilles Number
- no
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- yes
- Odd
- no
Appears in sequences
- Coordination sequence for hexagonal close-packing.at n=26A007899
- Coordination sequence for FeS2-Marcasite, Fe position.at n=44A009955
- a(0) = 1, a(n) = 42*n^2 + 2 for n>0.at n=13A010023
- Number of 5-tuples of different integers from [ 2,n ] with no common factors among pairs.at n=30A015699
- "DHK[ 8 ]" (bracelet, identity, unlabeled, 8 parts) transform of 1,1,1,1,...at n=11A032249
- Number of partitions satisfying cn(2,5) + cn(3,5) <= cn(0,5).at n=40A039861
- a(n) = Sum_{i=0..floor(n/2)} T(2i,n-2i), array T as in A048149.at n=29A049714
- Scaled Chebyshev U-polynomials evaluated at sqrt(10)/2.at n=4A057086
- Write 0,1,2,3,4,... in a triangular spiral; then a(n) is the sequence found by reading the terms along the line from 0 in the direction 0,2,...at n=40A062708
- Smallest multiple of n beginning with the n-th prime.at n=19A078208
- Greedy frac multiples of 1/Pi: a(1)=1, Sum_{n>0} frac(a(n)*x) = 1 at x=1/Pi, where "frac(y)" denotes the fractional part of y.at n=26A080142
- Numbers n such that ((n-1)^2+1)/2 and n^2+1 and ((n+1)^2+1)/2 are prime if n is even or (n-1)^2+1 and (n^2+1)/2 and (n+1)^2+1 are prime if n is odd.at n=36A082612
- Square number array read by antidiagonals.at n=41A084061
- Fourth row of number array A084061.at n=5A084065
- Least multiple of n == 1 (mod prime(n)).at n=49A090938
- G.f.: A(x) = Product_{n>=1} 1/(1 - A007947(n)*x^n)^(1/n), where A007947(n) is the product of the distinct prime factors of n.at n=23A094947
- Numbers n such that the numerator of BernoulliB[n] is divisible by 691.at n=26A119864
- Unsigned row sums of triangle A120078.at n=5A120079
- a(n) = T(p(n)) - p(T(n)) = Commutator[triangular numbers, primes] at n.at n=36A123907
- Numbers n where |sinc(n)| decreases monotonically to 0 (where sinc(x)=sin(x)/x).at n=45A131975