Properties of the Number 840

Eight Hundred Forty

Basics

Value: 839 → 840 → 841

Parity: even

Prime: No

Previous Prime: 839

Next Prime: 853

Digit Sum: 12

Digital Root: 3

Palindrome: No

Factorization: 2 ³ × 3 × 5 × 7

Divisors: 1, 2, 3, 4, 5, 6, 7, 8, 10, 12

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

8509 Try Today's Challenge

Representations

Binary: 1101001000

Octal: 1510

Duodecimal: 5A0

Hexadecimal: 348

Square: 705600

Square Root: 28.982753492378876

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

Least integer of each prime signature A124832; also products of primorial numbers A002110. A25487

Highly composite numbers: numbers n where d(n), the number of divisors of n (A000005), increases to a record. A2182

Least common multiple (or LCM) of {1, 2, ..., n} for n >= 1, a(0) = 1. A3418

a(n) = n*(n+2) = (n+1)² - 1. A5563

Numbers all of whose prime divisors are consecutive primes starting at 2. A55932

Smallest number with exactly n divisors. A5179

4 times triangular numbers: a(n) = 2·n*(n+1). A46092

Primorial inflation of n: Fully multiplicative with a(p) = p# for prime p, where x# is the primorial A034386(x). A108951

a(n) = smallest integer with factorization as Product p(i)^e(i) such that Product p(e(i)) = n. A181821

Triangle T(n,k) = n!/(n-k)! (0 <= k <= n) read by rows, giving number of permutations of n things k at a time. A8279