Properties of the Number 669

Six Hundred Sixty-Nine

Basics

Value: 668 → 669 → 670

Parity: odd

Prime: No

Previous Prime: 661

Next Prime: 673

Digit Sum: 21

Digital Root: 3

Palindrome: No

Factorization: 3 × 223

Divisors: 1, 3, 223, 669

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 1010011101

Octal: 1235

Duodecimal: 479

Hexadecimal: 29d

Square: 447561

Square Root: 25.865034312755125

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 partitions of n into distinct parts >= 2. A25147

a(n) = 3·prime(n). A1748

Irregular triangle read by rows with zeros removed where T(n,k) is the number of integer partitions of n with k distinct multiplicities, n > 0. A325242

Numbers k whose largest divisor <= sqrt(k) is 3. A161345

Numbers m such that the Bernoulli number B_2·m has denominator 42. A51227

a(n) = ∑_k=1..n π(k) (cf. A000720). A46992

Expansion of ∏_k>=1 Q(x^k)^k where Q(x) = ∏_k>=1 (1 + x^k). A192065

Carryless squares n X n base 10. A59729

Number of partitions of n into distinct parts, the least being 1. A96765

Coordination sequence for (3,3,5) tiling of hyperbolic plane. A265072