6647868 has 36 divisors (see below), whose sum is σ = 17166240. Its totient is φ = 2168256.

The previous prime is 6647831. The next prime is 6647869. The reversal of 6647868 is 8687466.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6647869) 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 11 ways as a sum of consecutive naturals, for example, 273 + ... + 3656.

It is an arithmetic number, because the mean of its divisors is an integer number (476840).

Almost surely, 2^6647868 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6647868, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8583120).

6647868 is an abundant number, since it is smaller than the sum of its proper divisors (10518372).

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

6647868 is a wasteful number, since it uses less digits than its factorization.

6647868 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3986 (or 3981 counting only the distinct ones).

The product of its digits is 387072, while the sum is 45.

The square root of 6647868 is about 2578.3459814385. The cubic root of 6647868 is about 188.0301370127.

The spelling of 6647868 in words is "six million, six hundred forty-seven thousand, eight hundred sixty-eight".