Properties of the Number 628

Six Hundred Twenty-Eight

Basics

Value: 627 → 628 → 629

Parity: even

Prime: No

Previous Prime: 619

Next Prime: 631

Digit Sum: 16

Digital Root: 7

Palindrome: No

Factorization: 2 ² × 157

Divisors: 1, 2, 4, 157, 314, 628

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

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Representations

Binary: 1001110100

Octal: 1164

Duodecimal: 444

Hexadecimal: 274

Square: 394384

Square Root: 25.059928172283335

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

Sum of totient function: a(n) = ∑_k=1..n φ(k), cf. A000010. A2088

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

Number of compositions of n if all summand runs are kept together. A274174

a(n) = binomial(n+1, 2) + n - 1 = n*(n+3)/2 - 1. A34856

Untouchable numbers, also called nonaliquot numbers: impossible values for the sum of aliquot parts function (A001065). A5114

Numbers that are the sum of 4 nonzero 4th powers. A3338

Numbers m such that the Bernoulli number B_2·m has denominator 30. A51225

Number of partitions of n in which no parts are multiples of 5. A35959

a(n) = n² + 3. A117950

Number of integer partitions of n whose product is a perfect power. A320322