678385 has 16 divisors (see below), whose sum is σ = 902016. Its totient is φ = 487168.

The previous prime is 678383. The next prime is 678401. The reversal of 678385 is 583876.

678385 = T₆₇₁ + T₆₇₂ + T₆₇₃.

It is a cyclic number.

It is not a de Polignac number, because 678385 - 2¹ = 678383 is a prime.

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

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (678383) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1782 + ... + 2128.

It is an arithmetic number, because the mean of its divisors is an integer number (56376).

2⁶⁷⁸³⁸⁵ is an apocalyptic number.

678385 is the 673-rd centered triangular number.

It is an amenable number.

678385 is a deficient number, since it is larger than the sum of its proper divisors (223631).

678385 is a wasteful number, since it uses less digits than its factorization.

678385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 392.

The product of its digits is 40320, while the sum is 37.

The square root of 678385 is about 823.6413054237. The cubic root of 678385 is about 87.8669217875.

The spelling of 678385 in words is "six hundred seventy-eight thousand, three hundred eighty-five".