911
domain: N
Properties
Digital Properties
- Digit Count
- 3
- Digit Sum
- 11
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 912
- Proper Divisor Sum (Aliquot Sum)
- 1
- 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
- 910
- Möbius Function
- -1
- Radical
- 911
- Omega Function (Ω)
- 1
- Little Omega Function (ω)
- 1
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
- 41
- Smith Number
- no
Primality
- Prime
- yes
- Composite Number
- no
- Semiprime
- no
- Squarefree Number
- yes
- Prime Power
- yes
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- yes
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 156
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Names
- German
- neunhundertelf· ordinal: neunhundertelfste
- English
- nine hundred eleven· ordinal: nine hundred eleventh
- Spanish
- novecientos once· ordinal: 911º
- French
- neuf cent onze· ordinal: neuf cent onzième
- Italian
- novecentoundici· ordinal: 911º
- Latin
- nongenti undecim· ordinal: 911.
- Portuguese
- novecentos e onze· ordinal: 911º
Appears in sequences
- Primes p == 3, 9, 11 (mod 20) such that 2p+1 is also prime.at n=16A000355
- Numbers beginning with letter 'n' in English.at n=23A000981
- Number of inverse semigroups of order n, considered to be equivalent when they are isomorphic or anti-isomorphic (by reversal of the operator).at n=6A001428
- Odd-indexed terms of A124297.at n=3A001604
- Cyclic numbers: 10 is a quadratic residue modulo p and class of mantissa is 2.at n=49A001914
- Lucasian primes: p == 3 (mod 4) with 2*p+1 prime.at n=18A002515
- Odd numbers written backwards.at n=59A004156
- Divisible only by primes congruent to 1 mod 5.at n=42A004615
- Numbers divisible only by primes congruent to 1 mod 7.at n=27A004619
- A sixth-order linear divisibility sequence: a(n+6) = -3*a(n+5) - 5*a(n+4) - 5*a(n+3) - 5*a(n+2) - 3*a(n+1) - a(n).at n=19A005120
- Sophie Germain primes p: 2p+1 is also prime.at n=35A005384
- Primes of the form k^2 + k + 41.at n=29A005846
- Primes of the form 8n+7, that is, primes congruent to -1 mod 8.at n=38A007522
- a(n) = largest prime factor of n^n + 1.at n=6A007571
- Primitive modest numbers.at n=36A007627
- Primes of the form 2*k^2 + 29.at n=21A007641
- Coordination sequence T1 for Zeolite Code APD.at n=20A008034
- Coordination sequence T8 for Zeolite Code EUO.at n=19A008103
- Coordination sequence T1 for Zeolite Code LTL.at n=22A008138
- Coordination sequence T8 for Zeolite Code PAU.at n=22A008226