1513
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 10
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 1620
- Proper Divisor Sum (Aliquot Sum)
- 107
- 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
- 1408
- Möbius Function
- 1
- Radical
- 1513
- 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
- 65
- 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 n-step spiral self-avoiding walks on hexagonal lattice, where at each step one may continue in same direction or make turn of 2*Pi/3 counterclockwise.at n=23A000511
- Number of permutations of length n with longest increasing subsequence of length 7.at n=2A001458
- Centered square numbers: a(n) = 2*n*(n+1)+1. Sums of two consecutive squares. Also, consider all Pythagorean triples (X, Y, Z=Y+1) ordered by increasing Z; then sequence gives Z values.at n=27A001844
- Generalized Euler numbers.at n=3A002115
- Numbers that are the sum of 6 positive 5th powers.at n=39A003351
- Pentagonal numbers written backwards.at n=46A004163
- Number of nonsplit type 2 metacyclic 2-groups of order 2^n.at n=49A007981
- Expansion of 1/(1-x^7-x^8-x^9-x^10-x^11-x^12-x^13-x^14-x^15).at n=45A017864
- a(n+1) (n >= 1) is smallest number > a(n) which is the sum of cubes of distinct earlier terms.at n=31A019511
- Pseudoprimes to base 52.at n=7A020180
- Pseudoprimes to base 55.at n=18A020183
- Pseudoprimes to base 77.at n=13A020205
- Strong pseudoprimes to base 55.at n=4A020281
- Strong pseudoprimes to base 77.at n=2A020303
- Numbers k such that the continued fraction for sqrt(k) has period 20.at n=37A020359
- Fibonacci sequence beginning 0, 17.at n=11A022351
- Place where n-th 1 occurs in A007337.at n=41A022777
- a(n+1) = a(n) converted to base 9 from base 7 (written in base 10).at n=16A023389
- a(n) = least m such that if r and s in {1/2, 1/4, 1/6,..., 1/2n} satisfy r < s, then r < k/m < s for some integer k.at n=31A024820
- a(n) = floor(floor(S3)/floor(S1)), where S3 and S1 are, respectively, the 3rd and first elementary symmetric functions of {sqrt(k), k = 1,2,...,n}.at n=25A025200