15851
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- yes
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 17556
- Proper Divisor Sum (Aliquot Sum)
- 1705
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 14300
- Möbius Function
- 0
- Radical
- 1441
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 58
- 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
- a(n) = (12*n+1)*(12*n+11).at n=10A001538
- a(n) = floor(n*(n-1)*(n-2)*(n-3)/31).at n=28A011941
- Numbers whose base-5 representation contains exactly three 0's and three 1's.at n=35A045172
- Numbers that are palindromic, divisible by 11 and have an odd number of digits.at n=13A045571
- Palindromes with exactly 3 palindromic prime factors (counted with multiplicity).at n=18A046377
- Consider all integer triples (i,j,k), j,k>0, with binomial(i+2,3)=binomial(j+2,3)+k^3, ordered by increasing i; sequence gives k values.at n=49A054223
- Numbers n for which there are exactly six k such that n = k + reverse(k).at n=36A072430
- Concatenation of palindrome k and its 10's complement is prime.at n=38A108537
- a(0)=1, a(1)=1, a(n) = 11*a(n/2) for even n, and a(n) = 10*a((n-1)/2) + a((n+1)/2) for odd n >= 3.at n=20A116525
- Numbers k that divide floor((4/3)^k).at n=12A118502
- Palindromic composites such that some digit permutation is prime.at n=39A119378
- a(n) = 15*n*(n+1) + 11.at n=32A132208
- Totally multiplicative sequence with a(p) = a(p-1) + 10 for prime p.at n=19A166707
- a(n) = Bell(n) - Sum_{j=0..n-1} Bell(j), where the Bell numbers are given in A000110.at n=9A171859
- Palindromic mountain numbers.at n=29A173070
- Nonprime numbers with all divisors starting and ending with digit 1.at n=27A208261
- Zeroless numbers n such that n and n - (product of digits of n) are both palindromes.at n=18A229761
- S_5 sequence in partition of integers > 1 described in A240521.at n=36A240522
- Numbers n for which the digital sum contains the same distinct digits as the digital product but the digital sum is not equal to the digital product.at n=27A249335
- Number of (n+2)X(n+2) 0..1 arrays with every 3X3 subblock sum of the two sums of the diagonal and antidiagonal minus the two minimums of the central column and central row nondecreasing horizontally, vertically and ne-to-sw antidiagonally.at n=13A254899