628985728 has 64 divisors (see below), whose sum is σ = 1507478400. Its totient is φ = 255370752.

The previous prime is 628985719. The next prime is 628985741. The reversal of 628985728 is 827589826.

It is a happy number.

628985728 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (64).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1450 + ... + 35497.

It is an arithmetic number, because the mean of its divisors is an integer number (23554350).

Almost surely, 2^628985728 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 628985728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (753739200).

628985728 is an abundant number, since it is smaller than the sum of its proper divisors (878492672).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

628985728 is a wasteful number, since it uses less digits than its factorization.

628985728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36987 (or 36975 counting only the distinct ones).

The product of its digits is 3870720, while the sum is 55.

The square root of 628985728 is about 25079.5878754018. The cubic root of 628985728 is about 856.8015899431.

The spelling of 628985728 in words is "six hundred twenty-eight million, nine hundred eighty-five thousand, seven hundred twenty-eight".