Properties of the Number 20047

Twenty Thousand Forty-Seven

Basics

Value: 20046 → 20047 → 20048

Parity: odd

Prime: Yes

Previous Prime: 20029

Next Prime: 20051

Digit Sum: 13

Digital Root: 4

Palindrome: No

Factorization: 20047

Divisors: 1, 20047

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

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Representations

Binary: 100111001001111

Octal: 47117

Duodecimal: B727

Hexadecimal: 4e4f

Square: 401882209

Square Root: 141.58742882049947

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

Luhn primes: primes p such that p + (p reversed) is also a prime. A61783

Values of y such that x² + y² = 17ⁿ with·and y coprime and 0 < x < y. A230623

Sums of 7 distinct powers of 3. A38469

Primes and their indices such that when their respective SOD's are both prime, the SOD of the index is the nextprime of the prime SOD. A117458

Sums of groups in A075635. A75636

a(n) = 13·n² + 7·n + 1. A168240

The number of integers m in the range 0 < m < 10ⁿ which are not divisible by any of their own digits (A038772). A327561

Primes p such that (3^p - 3^{(p + 1}/2) + 1)/7 is prime. A125743

a(n) = ∑_{k=0..floor(n/3)} (-1)^k * binomial(2·n-k+1,n-3·k). A371819

Integer part of log(n!)^{1 + log(1 + log(n})). A62443