749
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
- 4
- Divisor Sum
- 864
- Proper Divisor Sum (Aliquot Sum)
- 115
- 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
- 636
- Möbius Function
- 1
- Radical
- 749
- 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
- 46
- Smith 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
Names
- German
- siebenhundertneunundvierzig· ordinal: siebenhundertneunundvierzigste
- English
- seven hundred forty-nine· ordinal: seven hundred forty-ninth
- Spanish
- setecientos cuarenta y nueve· ordinal: 749º
- French
- sept cent quarante-neuf· ordinal: sept cent quarante-neufième
- Italian
- settecentoquarantanove· ordinal: 749º
- Latin
- septingenti quadraginta novem· ordinal: 749.
- Portuguese
- setecentos e quarenta e nove· ordinal: 749º
Appears in sequences
- Let A(n) = #{(i,j): i^2 + j^2 <= n}, V(n) = Pi*n, P(n) = A(n) - V(n); A000099 gives values of n where |P(n)| sets a new record; sequence gives A(A000099(n)).at n=12A000323
- Numbers m such that Fibonacci(m) ends with m.at n=28A000350
- Number of integral points in a certain sequence of closed quadrilaterals.at n=40A002579
- a(n) = C(n+2,3) + C(n,3) + C(n-1,3).at n=11A006004
- Number of ways writing 2^n as unordered sums of 2 primes.at n=17A006307
- a(n) = a(n-1) + a(n - 1 - number of even terms so far).at n=23A006336
- a(n) is the largest odd number k such that 9, 11, ..., k are sums of 3 of first n odd primes.at n=54A007962
- Coordination sequence T1 for Zeolite Code AFO.at n=18A008015
- Coordination sequence T1 for Zeolite Code MER.at n=20A008160
- Coordination sequence T2 for Zeolite Code PAU.at n=20A008220
- Coordination sequence T8 for Zeolite Code PAU.at n=20A008226
- Expansion of 1/( Product_{j=0..5} (1-x^(2*j+1)) ).at n=45A008675
- a(n) is the concatenation of n and 7n.at n=6A009441
- "Pascal sweep" for k=9: draw a horizontal line through the 1 at C(k,0) in Pascal's triangle; rotate this line and record the sum of the numbers on it (excluding the initial 1).at n=18A009540
- Coordination sequence T4 for Zeolite Code RUT.at n=18A009900
- Numbers k such that C(k,3) = C(x,3) + C(y,3) is solvable.at n=27A010330
- Numbers k such that phi(k) | sigma_13(k).at n=30A015771
- Numbers k such that phi(k + 11) | sigma(k).at n=27A015831
- Numbers k such that phi(k + 7) | sigma(k) for k not congruent to 0 (mod 3).at n=44A015848
- Four iterations of Reverse and Add are needed to reach a palindrome.at n=46A015980