6687618 has 72 divisors (see below), whose sum is σ = 16643088. Its totient is φ = 1785168.

The previous prime is 6687617. The next prime is 6687623. The reversal of 6687618 is 8167866.

It is a Harshad number since it is a multiple of its sum of digits (42).

Its product of digits (96768) is a multiple of the sum of its prime factors (108).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 6687618.

It is not an unprimeable number, because it can be changed into a prime (6687617) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 155505 + ... + 155547.

It is an arithmetic number, because the mean of its divisors is an integer number (231154).

Almost surely, 2^6687618 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6687618, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8321544).

6687618 is an abundant number, since it is smaller than the sum of its proper divisors (9955470).

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

6687618 is a wasteful number, since it uses less digits than its factorization.

6687618 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108 (or 78 counting only the distinct ones).

The product of its digits is 96768, while the sum is 42.

The square root of 6687618 is about 2586.0429230777. The cubic root of 6687618 is about 188.4041591934.

The spelling of 6687618 in words is "six million, six hundred eighty-seven thousand, six hundred eighteen".