678916393 has 4 divisors (see below), whose sum is σ = 679031748. Its totient is φ = 678801040.

The previous prime is 678916387. The next prime is 678916409. The reversal of 678916393 is 393619876.

678916393 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.

It can be written as a sum of positive squares in 2 ways, for example, as 159441129 + 519475264 = 12627^2 + 22792^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-678916393 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 678916393.

It is not an unprimeable number, because it can be changed into a prime (678916313) 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, 48346 + ... + 60787.

It is an arithmetic number, because the mean of its divisors is an integer number (169757937).

Almost surely, 2^678916393 is an apocalyptic number.

It is an amenable number.

678916393 is a deficient number, since it is larger than the sum of its proper divisors (115355).

678916393 is a wasteful number, since it uses less digits than its factorization.

678916393 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115354.

The product of its digits is 1469664, while the sum is 52.

The square root of 678916393 is about 26056.0241211126. The cubic root of 678916393 is about 878.8985845860.

The spelling of 678916393 in words is "six hundred seventy-eight million, nine hundred sixteen thousand, three hundred ninety-three".