947
domain: N
Properties
Digital Properties
- Digit Count
- 3
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 948
- 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
- 946
- Möbius Function
- -1
- Radical
- 947
- 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
- 36
- 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
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 161
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Names
- German
- neunhundertsiebenundvierzig· ordinal: neunhundertsiebenundvierzigste
- English
- nine hundred forty-seven· ordinal: nine hundred forty-seventh
- Spanish
- novecientos cuarenta y siete· ordinal: 947º
- French
- neuf cent quarante-sept· ordinal: neuf cent quarante-septième
- Italian
- novecentoquarantasette· ordinal: 947º
- Latin
- nongenti quadraginta septem· ordinal: 947.
- Portuguese
- novecentos e quarenta e sete· ordinal: 947º
Appears in sequences
- Primes that divide at least one term in every Fibonacci sequence.at n=36A000057
- Central polygonal numbers (the Lazy Caterer's sequence): n(n+1)/2 + 1; or, maximal number of pieces formed when slicing a pancake with n cuts.at n=43A000124
- E.g.f.: -log(1+log(1+log(1-x))).at n=4A000268
- Cyclic numbers: 10 is a quadratic residue modulo p and class of mantissa is 2.at n=52A001914
- Numbers k such that 4!*(2k-5)!/(k!*(k-1)!) is an integer.at n=6A004784
- 5!(2n-6)!/n!(n-1)! is an integer.at n=9A004785
- Class 3- primes (for definition see A005109).at n=49A005111
- G.f.: x*(1-x^2)*(x^4+x^3-x^2+x+1) / (x^8-4*x^6-x^4-4*x^2+1).at n=11A005822
- Primes p such that the NSW number A002315((p-1)/2) is prime.at n=11A005850
- Numbers k such that k-6, k, and k+6 are primes.at n=26A006489
- Balanced primes (of order one): primes which are the average of the previous prime and the following prime.at n=13A006562
- Maximal planar degree sequences with n nodes.at n=10A007020
- Add 2, then reverse digits!.at n=46A007396
- Inverse Moebius transform of triangular numbers.at n=42A007437
- Primes == 3 (mod 8).at n=42A007520
- Primes of form n^2 + n + 17.at n=26A007635
- Molien series for 4-dimensional complex reflection group of order 7680 (in powers of x^4).at n=50A008669
- If a, b in sequence, so is a*b+1.at n=52A009293
- Add 4, then reverse digits; start with 3.at n=20A016081
- Number of elements in the set {(x,y): 1 <= x,y <= n, gcd(x,y)=1}.at n=38A018805