678565 has 8 divisors (see below), whose sum is σ = 822168. Its totient is φ = 537600.

The previous prime is 678563. The next prime is 678577. The reversal of 678565 is 565876.

678565 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 91809 + 586756 = 303^2 + 766^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 678565 - 2¹ = 678563 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a zygodrome in base 4.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (678563) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36 + ... + 1165.

It is an arithmetic number, because the mean of its divisors is an integer number (102771).

2⁶⁷⁸⁵⁶⁵ is an apocalyptic number.

It is an amenable number.

678565 is a deficient number, since it is larger than the sum of its proper divisors (143603).

678565 is a wasteful number, since it uses less digits than its factorization.

678565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1319.

The product of its digits is 50400, while the sum is 37.

The square root of 678565 is about 823.7505690438. The cubic root of 678565 is about 87.8746925210.

The spelling of 678565 in words is "six hundred seventy-eight thousand, five hundred sixty-five".