• 628 can be written using four 4's:

See also 113.

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628 has 6 divisors (see below), whose sum is σ = 1106. Its totient is φ = 312.

The previous prime is 619. The next prime is 631. The reversal of 628 is 826.

628 is nontrivially palindromic in base 9 and base 12.

628 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

628 is an esthetic number in base 9, because in such base its adjacent digits differ by 1.

It can be written as a sum of positive squares in only one way, i.e., 484 + 144 = 22^2 + 12^2 .

628 is a Gilda number.

628 is an undulating number in base 9.

628 is a nontrivial repdigit in base 12.

It is a plaindrome in base 7, base 12 and base 15.

It is a nialpdrome in base 11 and base 12.

It is a zygodrome in base 12.

It is a congruent number.

It is an unprimeable number.

628 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 75 + ... + 82.

It is an amenable number.

628 is a deficient number, since it is larger than the sum of its proper divisors (478).

628 is a wasteful number, since it uses less digits than its factorization.

628 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 161 (or 159 counting only the distinct ones).

The product of its digits is 96, while the sum is 16.

The square root of 628 is about 25.0599281723. The cubic root of 628 is about 8.5635377114.

It can be divided in two parts, 62 and 8, that multiplied together give a triangular number (496 = T₃₁).

The spelling of 628 in words is "six hundred twenty-eight", and thus it is an aban number and an oban number.