Properties of the Number 20947

Twenty Thousand Nine Hundred Forty-Seven

Basics

Value: 20946 → 20947 → 20948

Parity: odd

Prime: Yes

Previous Prime: 20939

Next Prime: 20959

Digit Sum: 22

Digital Root: 4

Palindrome: No

Factorization: 20947

Divisors: 1, 20947

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101000111010011

Octal: 50723

Duodecimal: 10157

Hexadecimal: 51d3

Square: 438776809

Square Root: 144.73078456223473

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

Balanced primes of order eleven. A96703

T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with no 2X2 subblock having the sum of its diagonal elements greater than the maximum of its antidiagonal elements. A251137

Primes in A126554. A126555

The number of regions inside a concave circular triangle formed by the straight line segments mutually connecting all vertices and all points that divide the sides into n equal parts. A340685

Primes p such that 6p + 1 and (p-1)/6 are primes. A85957

Number of consecutive prime runs of 3 primes congruent to 3 mod 4 below 10ⁿ. A92643

Numerators in expansion of exp(2x)/(1-x). A53484

a(n) = A027052(n, 2n-2). A27058

Number of 2 X 2 matrices with all elements in {0,1,...,n} and determinant >= 2n. A210367

Expansion of ∏_k>=1 1/(1 + x^k)^k+1. A305628