1557
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 2262
- Proper Divisor Sum (Aliquot Sum)
- 705
- 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
- 1032
- Möbius Function
- 0
- Radical
- 519
- Omega Function (Ω)
- 3
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 122
- 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
- no
- Odd
- yes
Appears in sequences
- Spiral sieve using Fibonacci numbers.at n=15A005622
- a(n) = 3 + n/2 + 7*n^2/2.at n=21A006124
- Coordination sequence T1 for Zeolite Code AFR.at n=30A008019
- Coordination sequence T1 for Zeolite Code MFI.at n=25A008161
- Coordination sequence T5 for Zeolite Code NES.at n=25A008209
- Triangle T(n,k) read by rows, giving number of graphs with n nodes (n >= 1) and k edges (0 <= k <= n(n-1)/2).at n=78A008406
- Triangle T(n,k) read by rows, giving number of graphs with n nodes (n >= 1) and k edges (0 <= k <= n(n-1)/2).at n=76A008406
- Coordination sequence T3 for Zeolite Code RSN.at n=26A009887
- a(n) = n^2 + 3*n - 1.at n=38A014209
- Positive integers n such that 2^n (mod n) == 2^9 (mod n).at n=67A015931
- Pseudoprimes to base 80.at n=16A020208
- Numbers k such that the continued fraction for sqrt(k) has period 28.at n=23A020367
- Numbers k such that Fib(k) == -34 (mod k).at n=16A023169
- a(n+1) = a(n) converted to base 5 from base 4 (written in base 10).at n=16A023373
- a(n) = 1^2 + prime(1)^2 + prime(2)^2 + ... + prime(n)^2.at n=9A024525
- Numbers that are the sum of 3 nonzero squares in exactly 10 ways.at n=32A025330
- Numbers that are the sum of 3 distinct nonzero squares in exactly 10 ways.at n=32A025348
- Numbers k whose decimal representation, read as a base-13 value and divided by k, yields an integer.at n=9A032557
- Numbers whose set of base-6 digits is {1,3}.at n=31A032913
- Positions of incrementally largest terms in continued fraction for Copeland-Erdős constant.at n=9A033311