678911689 has 2 divisors, whose sum is σ = 678911690. Its totient is φ = 678911688.

The previous prime is 678911659. The next prime is 678911729. The reversal of 678911689 is 986119876.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 424030464 + 254881225 = 20592^2 + 15965^2 .

It is a cyclic number.

It is not a de Polignac number, because 678911689 - 2²⁵ = 645357257 is a prime.

It is not a weakly prime, because it can be changed into another prime (678911659) 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 as a sum of consecutive naturals, namely, 339455844 + 339455845.

It is an arithmetic number, because the mean of its divisors is an integer number (339455845).

Almost surely, 2^678911689 is an apocalyptic number.

It is an amenable number.

678911689 is a deficient number, since it is larger than the sum of its proper divisors (1).

678911689 is an equidigital number, since it uses as much as digits as its factorization.

678911689 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1306368, while the sum is 55.

The square root of 678911689 is about 26055.9338539228. The cubic root of 678911689 is about 878.8965547099.

The spelling of 678911689 in words is "six hundred seventy-eight million, nine hundred eleven thousand, six hundred eighty-nine".