628308891 has 48 divisors (see below), whose sum is σ = 1107325440. Its totient is φ = 335301120.

The previous prime is 628308859. The next prime is 628308911. The reversal of 628308891 is 198803826.

It is not a de Polignac number, because 628308891 - 2⁵ = 628308859 is a prime.

It is not an unprimeable number, because it can be changed into a prime (628303891) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 81291 + ... + 88683.

It is an arithmetic number, because the mean of its divisors is an integer number (23069280).

Almost surely, 2^628308891 is an apocalyptic number.

628308891 is a deficient number, since it is larger than the sum of its proper divisors (479016549).

628308891 is a wasteful number, since it uses less digits than its factorization.

628308891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7496 (or 7493 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 45.

The square root of 628308891 is about 25066.0904610192. The cubic root of 628308891 is about 856.4941515136.

The spelling of 628308891 in words is "six hundred twenty-eight million, three hundred eight thousand, eight hundred ninety-one".