Properties of the Number 20399

Twenty Thousand Three Hundred Ninety-Nine

Basics

Value: 20398 → 20399 → 20400

Parity: odd

Prime: Yes

Previous Prime: 20393

Next Prime: 20407

Digit Sum: 23

Digital Root: 5

Palindrome: No

Factorization: 20399

Divisors: 1, 20399

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 100111110101111

Octal: 47657

Duodecimal: B97B

Hexadecimal: 4faf

Square: 416119201

Square Root: 142.82506782774513

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

Primes p such that A001175(p) = (p-1)/7. A308792

Primes p such that A001177(p) = (p-1)/7. A308800

Prime number spiral (clockwise, Southeast spoke). A54564

Prime p1 of consecutive primes p1, p2, where p2 - p1 = 8, and p1, p2 are in different centuries. A287049

a(n) = A120963(2·n+1)/2. A341711

a(1)=2; a(n) for n>1 is the smallest prime number > a(n-1) such that the concatenation of all previous terms is also prime. A80155

Primes p that divide Fibonacci[(p-1)/7]. A125253

Primes p dividing every A167859(m) from m=(p-1)/2 to m=(p-1). A167860

Smallest prime p such that the multiplicative order of 9 modulo p is 2·n, or 0 if no such prime exists. A372799