197
domain: N
Properties
Digital Properties
- Digit Count
- 3
- Digit Sum
- 17
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 198
- 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
- 196
- Möbius Function
- -1
- Radical
- 197
- 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
- 26
- Smith Number
- no
Primality
- Prime
- yes
- Composite Number
- no
- Semiprime
- no
- Squarefree Number
- yes
- Prime Power
- yes
- Prime Factorization
- no
- Twin Prime
- yes
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 45
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Names
- German
- einshundertsiebenundneunzig· ordinal: einshundertsiebenundneunzigste
- English
- one hundred ninety-seven· ordinal: one hundred ninety-seventh
- Spanish
- ciento noventa y siete· ordinal: 197º
- French
- cent quatre-vingt-dix-sept· ordinal: cent quatre-vingt-dix-septième
- Italian
- centonovantasette· ordinal: 197º
- Latin
- centum nonaginta septem· ordinal: 197.
- Portuguese
- cento e noventa e sete· ordinal: 197º
Appears in sequences
- Coefficients of the 3rd-order mock theta function f(q).at n=37A000025
- Coefficient of q^(2n-1) in the series expansion of Ramanujan's mock theta function f(q).at n=18A000199
- Number of points of norm <= n^2 in square lattice.at n=8A000328
- Primes and squares of primes.at n=50A000430
- Number of steps to reach 1 in sequence A000546.at n=32A000547
- A Beatty sequence: [ n(e+1) ].at n=52A000572
- Number of partitions of n into prime parts.at n=36A000607
- n-th superior highly composite number A002201(n) is product of first n terms of this sequence.at n=67A000705
- Boustrophedon transform of natural numbers, cf. A000027.at n=5A000737
- Powers of primes. Alternatively, 1 and the prime powers (p^k, p prime, k >= 1).at n=59A000961
- a(n) = least m such that if a/b < c/d where a,b,c,d are integers in [0,n], then a/b < k/m < c/d for some integer k.at n=17A001000
- Schroeder's second problem (generalized parentheses); also called super-Catalan numbers or little Schroeder numbers.at n=5A001003
- Union of all numbers {p, q} where p and q are both primes or powers of primes and q = p+2.at n=43A001092
- Twin primes.at n=27A001097
- Primes with primitive root 2.at n=21A001122
- Number of graphical basis partitions of 2n.at n=13A001130
- Lesser of twin primes.at n=14A001359
- Partial sums of A001462; also a(n) is the last occurrence of n in A001462.at n=30A001463
- Numbers k such that phi(k+2) = phi(k) + 2.at n=24A001838
- The coding-theoretic function A(n,4,3).at n=34A001839