628557657 has 32 divisors (see below), whose sum is σ = 1033224192. Its totient is φ = 330986304.

The previous prime is 628557637. The next prime is 628557661. The reversal of 628557657 is 756755826.

It is a happy number.

It is not a de Polignac number, because 628557657 - 2⁷ = 628557529 is a prime.

It is not an unprimeable number, because it can be changed into a prime (628557637) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 196888 + ... + 200054.

It is an arithmetic number, because the mean of its divisors is an integer number (32288256).

Almost surely, 2^628557657 is an apocalyptic number.

It is an amenable number.

628557657 is a deficient number, since it is larger than the sum of its proper divisors (404666535).

628557657 is a wasteful number, since it uses less digits than its factorization.

628557657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3917.

The product of its digits is 3528000, while the sum is 51.

The square root of 628557657 is about 25071.0521717777. The cubic root of 628557657 is about 856.6071736876.

The spelling of 628557657 in words is "six hundred twenty-eight million, five hundred fifty-seven thousand, six hundred fifty-seven".