Properties of the Number 78439

Seventy-Eight Thousand Four Hundred Thirty-Nine

Basics

Value: 78438 → 78439 → 78440

Parity: odd

Prime: Yes

Previous Prime: 78437

Next Prime: 78467

Digit Sum: 31

Digital Root: 4

Palindrome: No

Factorization: 78439

Divisors: 1, 78439

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 10011001001100111

Octal: 231147

Duodecimal: 39487

Hexadecimal: 13267

Square: 6152676721

Square Root: 280.0696341983543

Classification

Fibonacci: No

Bell Number: No

Factorial Number: No

Regular Number: No

Perfect Number: No

Special

Kaprekar Constant: No

Munchausen Constant: No

Armstrong Number: No

Kaprekar Number: No

Catalan Number: No

Vampire Number: No

Taxicab Number: No

Super Prime: No

Friedman Number: No

Fermat Number: No

Cullen Number: No

OEIS Sequences

Smallest prime p > prime(n+2) such that p is a quadratic residue mod the first n odd primes 3, 5, 7, 11, ..., prime(n+1), and p is a quadratic non-residue mod prime(n+2). A96636

Nonsquare factors k > 0 such that k·x² - 1 produces a new minimum of its Hardy-Littlewood constant. A331948

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) = ∑_k>0 Kronecker(D,k)/k. A3421

Smallest prime p == 7 mod 8 (A007521) and p > prime(n+2) such that p is a quadratic residue mod the first n odd primes 3, 5, 7, 11, ..., prime(n+1), and p is a quadratic non-residue mod prime(n+2). A96640

Least prime p > prime(n+1) such that p is a square mod the first n odd primes 3, 5, 7, 11, ..., prime(n+1). A237436

Slowest increasing sequence of primes such that a(n - 1) + a(n) and a(n - 1)² + a(n)² are both semiprimes, with a(1)=2. A365050

Numbers n of the form 4·k+3 such that 2^m-1 == 1 (mod m) where m = (2·n-1)*n. A187923

a(n) = ∑_k=1..n gcd(k,n)*μ(gcd(k,n))². A78439

Number of nX4 0..4 arrays with each element·equal to the number its horizontal and vertical neighbors equal to 3,0,2,1,4 for x=0,1,2,3,4. A196481