Properties of the Number 71839

Seventy-One Thousand Eight Hundred Thirty-Nine

Basics

Value: 71838 → 71839 → 71840

Parity: odd

Prime: No

Previous Prime: 71837

Next Prime: 71843

Digit Sum: 28

Digital Root: 1

Palindrome: No

Factorization: 19 ² × 199

Divisors: 1, 19, 199, 361, 3781, 71839

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

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Representations

Binary: 10001100010011111

Octal: 214237

Duodecimal: 356A7

Hexadecimal: 1189f

Square: 5160841921

Square Root: 268.0279836136518

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

Consider all ways of writing a number as p+2m² where p is 1 or a prime and m >= 0; sequence gives numbers that are expressible in at least 2 more ways than any smaller number. A16067

a(n) = p²*(p²+2·p-1)/2, where p = prime(n). A229738

Square array A(n,k), n >= 1, k >= 1, read by antidiagonals downwards, where A(n,k) = n! * k! * [xⁿ * y^k] (1/2) * (1 / (exp(x) + exp(y) - exp(x+y))² - 1). A382740

a(n) = (n⁴ + 2·n³ - n²)/2. A255499

Composite numbers whose prime factors contain no digits other than 1 and 9. A36309

a(n) = q²*(q²+2·q-1)/2, where q = n-th prime power A000961(n). A229739

Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 55 ones. A31823

Number of primes == 1 mod 8 <= n. A71839