Properties of the Number 20787

Twenty Thousand Seven Hundred Eighty-Seven

Basics

Value: 20786 → 20787 → 20788

Parity: odd

Prime: No

Previous Prime: 20773

Next Prime: 20789

Digit Sum: 24

Digital Root: 6

Palindrome: No

Factorization: 3 × 13 ² × 41

Divisors: 1, 3, 13, 39, 41, 123, 169, 507, 533, 1599

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101000100110011

Octal: 50463

Duodecimal: 10043

Hexadecimal: 5133

Square: 432099369

Square Root: 144.17697458332242

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

30-gonal numbers: a(n) = n*(14·n-13). A254474

Numbers that are the sum of eight fourth powers in nine or more ways. A345584

Numbers that are the sum of eight fourth powers in ten or more ways. A345585

Number of partitions of n into parts not of the form 13k, 13k+6 or 13k-6. Also number of partitions with at most 5 parts of size 1 and differences between parts at distance 5 are greater than 1. A35954

a(n) = dot_product(1,2,...,n)*(5,6,...,n,1,2,3,4). A26043

Number of Carlitz compositions of n with exactly one descent. A241691

Number of partitions of n that contain more prime parts than nonprime parts. A355225

Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 25 ones. A31793

Surround numbers of an n X 2 rectangle when n is odd. A61525

Number of binary strings of length n with equal numbers of 00000 and 00010 substrings. A164179