678591349739 has 4 divisors (see below), whose sum is σ = 678657544656. Its totient is φ = 678525154824.

The previous prime is 678591349727. The next prime is 678591349753. The reversal of 678591349739 is 937943195876.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-678591349739 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (678591349939) 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, 33082079 + ... + 33102584.

It is an arithmetic number, because the mean of its divisors is an integer number (169664386164).

Almost surely, 2^678591349739 is an apocalyptic number.

678591349739 is a deficient number, since it is larger than the sum of its proper divisors (66194917).

678591349739 is a wasteful number, since it uses less digits than its factorization.

678591349739 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66194916.

The product of its digits is 308629440, while the sum is 71.

The spelling of 678591349739 in words is "six hundred seventy-eight billion, five hundred ninety-one million, three hundred forty-nine thousand, seven hundred thirty-nine".