3125
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 11
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 3906
- Proper Divisor Sum (Aliquot Sum)
- 781
- 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
- 2500
- Möbius Function
- 0
- Radical
- 5
- Omega Function (Ω)
- 5
- Little Omega Function (ω)
- 1
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
- 123
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- Prime Power
- yes
- 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
- no
- Odd
- yes
Appears in sequences
- a(n) = n^n; number of labeled mappings from n points to themselves (endofunctions).at n=5A000312
- Let A(n) = #{(i,j): i^2 + j^2 <= n}, V(n) = Pi*n, P(n) = A(n) - V(n); A000099 gives values of n where |P(n)| sets a new record; sequence gives A(A000099(n)).at n=21A000323
- Powers of 5: a(n) = 5^n.at n=5A000351
- Numbers that are the sum of 2 squares in exactly 3 ways.at n=33A000443
- Fifth powers: a(n) = n^5.at n=5A000584
- Numbers of the form 2^i*5^j with i, j >= 0.at n=37A003592
- Numbers of the form 3^i*5^j with i, j >= 0.at n=24A003593
- Numbers of the form 5^i*7^j with i, j >= 0.at n=15A003595
- Numbers of the form 5^i * 11^j.at n=13A003598
- Square array read by upwards antidiagonals: T(n,k) = n^k for n >= 0, k >= 0.at n=60A003992
- Array read by ascending antidiagonals: A(n, k) = k^n.at n=60A004248
- Numbers that are the sum of at most 2 positive 5th powers.at n=15A004842
- Numbers that are the sum of at most 3 positive 5th powers.at n=35A004843
- Smallest label f(T) given to a rooted tree T with n nodes in Matula-Goebel labeling.at n=15A005517
- Least hypotenuse of n distinct Pythagorean triangles.at n=5A006339
- a(n) = floor(n/5)*floor((n+1)/5)*floor((n+2)/5)*floor((n+3)/5)*floor((n+4)/5).at n=25A008382
- Integers of the form Product p_j^k_j = Product k_j^p_j; p_j in A000040.at n=8A008478
- Fibonacci number F(n) to power F(n).at n=5A008973
- Triangle in which j-th entry in i-th row is (j+1)^(i-j).at n=49A009998
- Triangle in which j-th entry in i-th row is (i+1-j)^j, 0<=j<=i.at n=50A009999