Properties of the Number 28157

Twenty-Eight Thousand One Hundred Fifty-Seven

Basics

Value: 28156 → 28157 → 28158

Parity: odd

Prime: No

Previous Prime: 28151

Next Prime: 28163

Digit Sum: 23

Digital Root: 5

Palindrome: No

Factorization: 37 × 761

Divisors: 1, 37, 761, 28157

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 110110111111101

Octal: 66775

Duodecimal: 14365

Hexadecimal: 6dfd

Square: 792816649

Square Root: 167.80047675736802

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

Number of prime powers p^k (k ≠ 1) <= 10ⁿ. A76048

Irregular triangular array: row n gives numbers D, each being the discriminant of the minimal polynomial of a quadratic irrational represented by a continued fraction with period an n-tuple of 1s and 3s. A246921

Irregular triangular array: every periodic simple continued fraction CF represents a quadratic irrational (c + f·sqrt(d))/b, where b,c,f,d are integers and d is squarefree. Row n of this array shows the distinct values of d as CF ranges through the periodic continued fractions having period an n-tuple of 1s and 3s. A246922

Expansion of 1/(1 - x - x³ + x⁵). A123552

a(n) = 78·n² - 1. A158771

Duplicate of A076048. A77270

1 and the prime powers p^m where m >= 2, thus excluding the primes. A25475

Expansion of 1/((1-4·x)*(1-8·x)*(1-9·x)*(1-12·x)). A28157