678888889 has 4 divisors (see below), whose sum is σ = 775873024. Its totient is φ = 581904756.

The previous prime is 678888877. The next prime is 678888923. The reversal of 678888889 is 988888876.

678888889 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 678888889 - 2⁵ = 678888857 is a prime.

It is a Duffinian number.

It is a plaindrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (678888389) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 48492057 + ... + 48492070.

It is an arithmetic number, because the mean of its divisors is an integer number (193968256).

Almost surely, 2^678888889 is an apocalyptic number.

It is an amenable number.

678888889 is a deficient number, since it is larger than the sum of its proper divisors (96984135).

678888889 is an equidigital number, since it uses as much as digits as its factorization.

678888889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96984134.

The product of its digits is 99090432, while the sum is 70.

The square root of 678888889 is about 26055.4963299493. The cubic root of 678888889 is about 878.8867158918.

The spelling of 678888889 in words is "six hundred seventy-eight million, eight hundred eighty-eight thousand, eight hundred eighty-nine".