751
domain: N
Properties
Digital Properties
- Digit Count
- 3
- Digit Sum
- 13
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 752
- 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
- 750
- Möbius Function
- -1
- Radical
- 751
- 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
- 139
- 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
- 133
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Names
- German
- siebenhunderteinundfünfzig· ordinal: siebenhunderteinundfünfzigste
- English
- seven hundred fifty-one· ordinal: seven hundred fifty-first
- Spanish
- setecientos cincuenta y uno· ordinal: 751º
- French
- sept cent cinquante et un· ordinal: sept cent cinquante et unième
- Italian
- settecentocinquantuno· ordinal: 751º
- Latin
- septingenti quinquaginta unus· ordinal: 751.
- Portuguese
- setecentos e cinquenta e um· ordinal: 751º
Appears in sequences
- Number of n-step spiral self-avoiding walks on hexagonal lattice, where at each step one may continue in same direction or make turn of 2*Pi/3 counterclockwise.at n=20A000511
- Primes p of the form 3k+1 such that sum_{x=1..p} cos(2*Pi*x^3/p) < -sqrt(p).at n=12A000923
- Irregular primes: primes p such that at least one of the numerators of the Bernoulli numbers B_2, B_4, ..., B_{p-3} (A000367) is divisible by p.at n=48A000928
- Primes with 3 as smallest primitive root.at n=31A001123
- Numerators of Cotesian numbers (not in lowest terms): A002176(n)*C(n,0).at n=6A002177
- Primes of the form 2^q*3^r*5^s + 1.at n=31A002200
- Numbers k such that the Woodall number k*2^k - 1 is prime.at n=13A002234
- Numbers k such that (k^2 + k + 1)/21 is prime.at n=37A002644
- Primes p with a Fibonacci primitive root g, i.e., such that g^2 = g + 1 (mod p).at n=41A003147
- G.f.: (1 + x^3 + x^4 + ... + x^12 + x^15)/Product_{i=1..10} (1 - x^i).at n=17A003403
- Nonsquare values of m in the discriminant D = 4*m leading to a new maximum of the L-function of the Dirichlet series L(1) = Sum_{k>0} Kronecker(D,k)/k.at n=18A003421
- Primes written backwards.at n=36A004087
- Divisible only by primes congruent to 1 mod 5.at n=36A004615
- a(n) = floor(n*phi^8), where phi is the golden ratio, A001622.at n=16A004923
- Fortunate numbers: least m > 1 such that m + prime(n)# is prime, where p# denotes the product of all primes <= p.at n=43A005235
- Emirps (primes whose reversal is a different prime).at n=25A006567
- Oscillates under partition transform.at n=28A007210
- Primes whose reversal in base 10 is also prime (called "palindromic primes" by David Wells, although that name usually refers to A002385). Also called reversible primes.at n=40A007500
- Primes of the form 8n+7, that is, primes congruent to -1 mod 8.at n=33A007522
- Primes of the form 2*k^2 + 29.at n=19A007641