678618 has 40 divisors (see below), whose sum is σ = 1568160. Its totient is φ = 219240.

The previous prime is 678611. The next prime is 678631. The reversal of 678618 is 816876.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

Its product of digits (16128) is a multiple of the sum of its prime factors (144).

It is not an unprimeable number, because it can be changed into a prime (678611) by changing a digit.

678618 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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 19 ways as a sum of consecutive naturals, for example, 9523 + ... + 9593.

It is an arithmetic number, because the mean of its divisors is an integer number (39204).

2⁶⁷⁸⁶¹⁸ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 678618, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (784080).

678618 is an abundant number, since it is smaller than the sum of its proper divisors (889542).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

678618 is a wasteful number, since it uses less digits than its factorization.

678618 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 144 (or 135 counting only the distinct ones).

The product of its digits is 16128, while the sum is 36.

The square root of 678618 is about 823.7827383479. The cubic root of 678618 is about 87.8769803085.

It can be divided in two parts, 678 and 618, that added together give a 4-th power (1296 = 6⁴).

The spelling of 678618 in words is "six hundred seventy-eight thousand, six hundred eighteen".