Properties of the Number 1540

One Thousand Five Hundred Forty

Basics

Value: 1539 → 1540 → 1541

Parity: even

Prime: No

Previous Prime: 1531

Next Prime: 1543

Digit Sum: 10

Digital Root: 1

Palindrome: No

Factorization: 2 ² × 5 × 7 × 11

Divisors: 1, 2, 4, 5, 7, 10, 11, 14, 20, 22

Polygonal

Triangular: Yes

Square: No

Pentagonal: No

Hexagonal: Yes

Heptagonal: No

Tetrahedral: Yes

Today's Target

2730 Try Today's Challenge

Representations

Binary: 11000000100

Octal: 3004

Duodecimal: A84

Hexadecimal: 604

Square: 2371600

Square Root: 39.242833740697165

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

Tetrahedral (or triangular pyramidal) numbers: a(n) = C(n+2,3) = n*(n+1)*(n+2)/6. A292

Hexagonal numbers: a(n) = n*(2·n-1). A384

10-gonal (or decagonal) numbers: a(n) = n*(4·n-3). A1107

Numbers having k prime factors (counted with multiplicity), the largest of which is the k-th prime. A106529

Landau's function g(n): largest order of permutation of n elements. Equivalently, largest LCM of partitions of n. A793

Generalized 10-gonal numbers: m*(4·m - 3) for m = 0, +- 1, +- 2, +- 3, ... A74377

Coordination sequence T1 for Zeolite Code LTA and ρ. A8137

Doubly triangular numbers: a(n) = n*(n+1)*(n²+n+2)/8. A2817

Centered 9-gonal (also known as nonagonal or enneagonal) numbers. Every third triangular number, starting with a(1)=1. A60544

Expansion of g.f. x*(1 + 3·x)/((1 + x)*(1 - x)³). A35608