1587
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 2212
- Proper Divisor Sum (Aliquot Sum)
- 625
- 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
- 1012
- Möbius Function
- 0
- Radical
- 69
- 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
- 78
- 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
- Numbers that are the sum of 5 positive 6th powers.at n=13A003361
- Numbers that are the sum of at most 5 nonzero 6th powers.at n=44A004856
- Expansion of (1+2*x+3*x^2)/((1-x)*(1-x^2)^2).at n=45A014255
- Odd numbers k such that d(k) does not divide phi(k).at n=41A015734
- Expansion of 1/((1-2x)*(1-4x)*(1-9x)).at n=3A016291
- Positive integers which apparently never result in a palindrome under repeated applications of the function A056964(x) = x + (x with digits reversed).at n=16A023108
- S(n,1) + S(n-1,2) + S(n-2,3) + ... + S(n+1-k,k), where k = floor((n+1)/2) and S(i,j) are Stirling numbers of the second kind.at n=9A024427
- Index of 10^n within the sequence of the numbers of the form 9^i*10^j.at n=54A025747
- a(n) = (d(n)-r(n))/2, where d = A026060 and r is the periodic sequence with fundamental period (1,0,0,0).at n=18A026061
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 13.at n=17A031511
- Lucky numbers with size of gaps equal to 10 (lower terms).at n=18A031892
- a(n) = n^2 - floor((n+1)/2)^2.at n=46A032438
- Quotient of 'base-23' division described in A032577.at n=48A032578
- Lucky numbers ending with digit 7.at n=40A032588
- Numbers whose set of base-5 digits is {2,3}.at n=34A032805
- a(n) = 3*n^2.at n=23A033428
- Number of partitions of n with equal number of parts congruent to each of 0, 1 and 3 (mod 5).at n=45A035573
- First differences of A037257.at n=47A037258
- Positive numbers having the same set of digits in base 4 and base 6.at n=45A037424
- List of pairs of consecutive numbers each with 6 divisors (duplicates removed).at n=51A038400