Properties of the Number 1247

One Thousand Two Hundred Forty-Seven

Basics

Value: 1246 → 1247 → 1248

Parity: odd

Prime: No

Previous Prime: 1237

Next Prime: 1249

Digit Sum: 14

Digital Root: 5

Palindrome: No

Factorization: 29 × 43

Divisors: 1, 29, 43, 1247

Polygonal

Triangular: No

Square: No

Pentagonal: Yes

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 10011011111

Octal: 2337

Duodecimal: 87B

Hexadecimal: 4df

Square: 1555009

Square Root: 35.31288716601915

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

Pentagonal numbers: a(n) = n*(3·n-1)/2. A326

Generalized pentagonal numbers: m*(3·m - 1)/2, m = 0, +-1, +-2, +-3, .... A1318

Numbers that are the sum of 6 positive 5th powers. A3351

a(n) = (prime(n)² - 1)/24. A24702

Expansion of g.f. (1 + x + 2·x²)/((1 - x)²*(1 - x³)). A969

Sum of first n semiprimes. A62198

Number of partitions-into-distinct-parts of n (A000009) is a prime. A35359

Pentagonal numbers with odd index: a(n) = (2·n+1)*(3·n+1). A33570

a(n) = n*(n + 14). A98848

Number of simple connected graphs g on n nodes with |Aut(g)| = 24. A241463