Properties of the Number 455

Four Hundred Fifty-Five

Basics

Value: 454 → 455 → 456

Parity: odd

Prime: No

Previous Prime: 449

Next Prime: 457

Digit Sum: 14

Digital Root: 5

Palindrome: No

Factorization: 5 × 7 × 13

Divisors: 1, 5, 7, 13, 35, 65, 91, 455

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: Yes

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Representations

Binary: 111000111

Octal: 707

Duodecimal: 31B

Hexadecimal: 1c7

Square: 207025

Square Root: 21.330729007701542

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

a(n) = sigma₂(n): sum of squares of divisors of n. A1157

The squarefree numbers ordered lexicographically by their prime factorization (with factors written in decreasing order). a(n) = ∏_{k in I} prime(k+1), where I is the set of indices of nonzero binary digits in n = ∑_{k in I} 2^k. A19565

Binary palindromes: numbers whose binary expansion is palindromic. A6995

Triangle of Mahonian numbers T(n,k): coefficients in expansion of ∏_i=0..n-1 (1 + x + ... + xⁱ), where k ranges from 0 to A000217(n-1). Also enumerates permutations by their major index. A8302

Numbers k such that the sum of the squares of the first k primes is divisible by k. A111441

a(n) is the smallest m > 1 such that m divides ∑_k=1..m prime(k)ⁿ. A85450

a(n) = 1² + 3² + 5² + 7² + ... + (2·n-1)² = n*(4·n² - 1)/3. A447

Number of parts in all partitions of n into distinct parts. A15723

The game of Mousetrap with n cards (given n letters and n envelopes, how many ways are there to fill the envelopes so that at least one letter goes into its right envelope?). A2467