Properties of the Number 20158

Twenty Thousand One Hundred Fifty-Eight

Basics

Value: 20157 → 20158 → 20159

Parity: even

Prime: No

Previous Prime: 20149

Next Prime: 20161

Digit Sum: 16

Digital Root: 7

Palindrome: No

Factorization: 2 × 10079

Divisors: 1, 2, 10079, 20158

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 100111010111110

Octal: 47276

Duodecimal: B7BA

Hexadecimal: 4ebe

Square: 406344964

Square Root: 141.97887166758298

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

G.f. satisfies: A(x) = 1 + x·A(x)³*A(x·A(x)³). A215505

Numbers k such that k divides the sum of digits in factorial base of all numbers from 1 to k. A333702

The smallest number such that n or more numbers k exist with k - a(n) = sopfr(k) + sopfr(a(n)), where sopfr(m) is the sum of the primes dividing m with repetition. A370352

Solution of the complementary equation a(n) = 3·a(n-2) + b(n-2), where a(0) = 1, a(1) = 2, b(0) = 3, b(1) = 4, and (a(n)) and (b(n)) are increasing complementary sequences. A295139

Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 619", based on the 5-celled von Neumann neighborhood. A273252

a(n) is the smallest number such that exactly n numbers k exist with k - a(n) = sopfr(k) + sopfr(a(n)), where sopfr(m) is the sum of the primes dividing m with repetition. A370356

a(1) = 1; a(n+1) = sum of terms in continued fraction for the sum of the continued fractions, [a(1); a(2), a(3),...,a(n-1),a(n)] and [a(n); a(n-1), a(n-2),...,a(2), a(1)]. A58081

Number of permutations of length n which avoid the patterns 1234, 3421, 4312. A116756

Choix de Bruxelles (version 1): irregular table read by rows in which row n lists all the legal numbers that can be reached by halving or doubling some substring of the decimal expansion of n. A323286

Pseudoprimes to base 30. A20158