685628889 has 48 divisors (see below), whose sum is σ = 1069482240. Its totient is φ = 387335520.

The previous prime is 685628861. The next prime is 685628917. The reversal of 685628889 is 988826586.

It is an interprime number because it is at equal distance from previous prime (685628861) and next prime (685628917).

It is not a de Polignac number, because 685628889 - 2⁷ = 685628761 is a prime.

It is a Smith number, since the sum of its digits (60) 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 (685628849) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 797742 + ... + 798600.

It is an arithmetic number, because the mean of its divisors is an integer number (22280880).

Almost surely, 2^685628889 is an apocalyptic number.

It is an amenable number.

685628889 is a deficient number, since it is larger than the sum of its proper divisors (383853351).

685628889 is a wasteful number, since it uses less digits than its factorization.

685628889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 978 (or 959 counting only the distinct ones).

The product of its digits is 13271040, while the sum is 60.

The square root of 685628889 is about 26184.5162071022. The cubic root of 685628889 is about 881.7856686335.

The spelling of 685628889 in words is "six hundred eighty-five million, six hundred twenty-eight thousand, eight hundred eighty-nine".