Properties of the Number 1664

One Thousand Six Hundred Sixty-Four

Basics

Value: 1663 → 1664 → 1665

Parity: even

Prime: No

Previous Prime: 1663

Next Prime: 1667

Digit Sum: 17

Digital Root: 8

Palindrome: No

Factorization: 2 ⁷ × 13

Divisors: 1, 2, 4, 8, 13, 16, 26, 32, 52, 64

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

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Representations

Binary: 11010000000

Octal: 3200

Duodecimal: B68

Hexadecimal: 680

Square: 2768896

Square Root: 40.792156108742276

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

Numbers k that divide the (left) concatenation of all numbers <= k written in base 25 (most significant digit on left). A29494

Numbers that are divisible by exactly 8 primes counting multiplicity. A46310

Numbers k such that the k-th composition in standard order is strictly increasing. A333255

Numbers with an even number of prime factors (counted with multiplicity) that cannot be factored into distinct semiprimes. A320892

Multiples of 16 containing a 16 in their decimal representation. A121036

Number of superdiagonal bargraphs with area n. A219282

a(n) = 2ⁿ * Fibonacci(n). A103435

a(n) = 2ⁿ*Bell(n). E.g.f.: exp(exp(2·x)-1). A55882

Distribute the natural numbers in columns based on the occurrence of "2" in each prime factorization; square array A(row,col) = 2^row-1 * ((2·col)-1), read by descending antidiagonals. A135764

a(n) = ∑_{d∣n, n/d == 1 (mod 4)} d² - ∑_{d∣n, n/d == 3 (mod 4)} d². A50470