678579493 has 4 divisors (see below), whose sum is σ = 680593420. Its totient is φ = 676565568.

The previous prime is 678579449. The next prime is 678579529. The reversal of 678579493 is 394975876.

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 213832129 + 464747364 = 14623^2 + 21558^2 .

It is a cyclic number.

It is not a de Polignac number, because 678579493 - 2²⁵ = 645025061 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (678579403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1006458 + ... + 1007131.

It is an arithmetic number, because the mean of its divisors is an integer number (170148355).

Almost surely, 2^678579493 is an apocalyptic number.

It is an amenable number.

678579493 is a deficient number, since it is larger than the sum of its proper divisors (2013927).

678579493 is a wasteful number, since it uses less digits than its factorization.

678579493 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2013926.

The product of its digits is 11430720, while the sum is 58.

The square root of 678579493 is about 26049.5584031668. The cubic root of 678579493 is about 878.7531813483.

The spelling of 678579493 in words is "six hundred seventy-eight million, five hundred seventy-nine thousand, four hundred ninety-three".