678909 has 16 divisors (see below), whose sum is σ = 1128960. Its totient is φ = 352560.

The previous prime is 678907. The next prime is 678941. The reversal of 678909 is 909876.

It is not a de Polignac number, because 678909 - 2¹ = 678907 is a prime.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (678901) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1239 + ... + 1700.

It is an arithmetic number, because the mean of its divisors is an integer number (70560).

2⁶⁷⁸⁹⁰⁹ is an apocalyptic number.

It is an amenable number.

678909 is a deficient number, since it is larger than the sum of its proper divisors (450051).

678909 is a wasteful number, since it uses less digits than its factorization.

678909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2960.

The product of its (nonzero) digits is 27216, while the sum is 39.

The square root of 678909 is about 823.9593436572. The cubic root of 678909 is about 87.8895394345.

The spelling of 678909 in words is "six hundred seventy-eight thousand, nine hundred nine".