13657
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 22
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 15616
- Proper Divisor Sum (Aliquot Sum)
- 1959
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 11700
- Möbius Function
- 1
- Radical
- 13657
- 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
- 45
- 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
- a(n) = self-convolution of row n of array T given by A027052.at n=8A027072
- Lucky numbers with size of gaps equal to 20 (lower terms).at n=27A031902
- Number of horizontally convex n-ominoes in which the top row has exactly 1 square, which is not above the rightmost square in the second row and the rightmost square in the second row is above the leftmost square in the third row.at n=11A049222
- G.f.: Sum_{n >= 1} x^n/(1-x^n)^5.at n=21A073570
- Number of n-node triangulations of the nonorientable surface N_4 in which every node has degree >= 3.at n=2A129053
- Triangle, read by rows, where row n equals row n of matrix power A132844^n for n>=0, where triangle A132844 is defined by: A132844(n,k) = T( [(n+k)/2], k) for n>=k>=0.at n=29A132845
- Column 1 of triangle A132845.at n=6A132847
- Numbers such that n^2 = 29 mod 1193.at n=22A165989
- Number of ordered triples (w,x,y) with all terms in {1,...,n} and 2w^2>x^2+y^2.at n=30A211810
- Number of partitions of n where the difference between consecutive parts is at most 7.at n=36A238867
- Number of colored compositions using all colors of an n-set such that all parts have different color patterns and the patterns for parts i have i distinct colors in increasing order.at n=3A327585
- Number of ways to write n as an ordered sum of seven positive Fibonacci numbers (with a single type of 1).at n=29A357694