628865840 has 20 divisors (see below), whose sum is σ = 1462113264. Its totient is φ = 251546304.

The previous prime is 628865827. The next prime is 628865849. The reversal of 628865840 is 48568826.

It is a tau number, because it is divible by the number of its divisors (20).

It is a Smith number, since the sum of its digits (47) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (628865849) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3930332 + ... + 3930491.

Almost surely, 2^628865840 is an apocalyptic number.

It is an amenable number.

628865840 is an abundant number, since it is smaller than the sum of its proper divisors (833247424).

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

628865840 is a wasteful number, since it uses less digits than its factorization.

628865840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7860836 (or 7860830 counting only the distinct ones).

The product of its (nonzero) digits is 737280, while the sum is 47.

The square root of 628865840 is about 25077.1976105784. The cubic root of 628865840 is about 856.7471495155.

The spelling of 628865840 in words is "six hundred twenty-eight million, eight hundred sixty-five thousand, eight hundred forty".