10101
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 3
- Digital Root
- 3
- Palindromic Number
- yes
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 17024
- Proper Divisor Sum (Aliquot Sum)
- 6923
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 5184
- Möbius Function
- 1
- Radical
- 10101
- Omega Function (Ω)
- 4
- Little Omega Function (ω)
- 4
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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 42
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- 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
- Strobogrammatic numbers: the same upside down.at n=40A000787
- Numbers whose square is a palindrome.at n=21A002778
- Numbers whose cube is a palindrome.at n=10A002780
- Least positive multiple of n written in base 4 using only 0 and 1.at n=38A004284
- Least positive multiple of n that when written in base 10 uses only 0's and 1's.at n=20A004290
- Fibonacci numbers written in base 2.at n=8A004685
- Numbers with mirror symmetry about middle.at n=18A006072
- The binary numbers (or binary words, or binary vectors, or binary expansion of n): numbers written in base 2.at n=21A007088
- a(n) = a(n-2) + a(n-3), with a(0) = 0, a(1) = 1, a(2) = 4.at n=32A007309
- Number of matchings in rooted plane trees on n nodes.at n=7A007859
- n written in base where place values are positive squares.at n=34A007961
- Expansion of 1/((1-x)^3*(1-x^3)^2).at n=34A011779
- Representation of n in base of Fibonacci numbers (the Zeckendorf representation of n). Also, binary words starting with 1 not containing 11, with the word 0 added.at n=12A014417
- Binary reflected Gray code.at n=25A014550
- Erroneous version of A307102.at n=18A019513
- Divisors of 999999.at n=49A027892
- Palindromes of form k^2 + k + 1.at n=6A028414
- Numbers k such that k^2 is a palindrome with an odd number of digits.at n=20A028816
- Distinct odd numbers in (2,3)-Pascal triangle A029600.at n=50A029608
- Odd numbers to the left of the central elements of the (2,3)-Pascal triangle A029600.at n=33A029612