678591 has 16 divisors (see below), whose sum is σ = 1031520. Its totient is φ = 440640.

The previous prime is 678581. The next prime is 678593. The reversal of 678591 is 195876.

678591 is a `hidden beast` number, since 67 + 8 + 591 = 666.

It is not a de Polignac number, because 678591 - 2⁷ = 678463 is a prime.

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 (678593) 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 15 ways as a sum of consecutive naturals, for example, 801 + ... + 1413.

It is an arithmetic number, because the mean of its divisors is an integer number (64470).

2⁶⁷⁸⁵⁹¹ is an apocalyptic number.

678591 is a deficient number, since it is larger than the sum of its proper divisors (352929).

678591 is a wasteful number, since it uses less digits than its factorization.

678591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 663 (or 657 counting only the distinct ones).

The product of its digits is 15120, while the sum is 36.

The square root of 678591 is about 823.7663503688. The cubic root of 678591 is about 87.8758148468.

The spelling of 678591 in words is "six hundred seventy-eight thousand, five hundred ninety-one".