6688740 has 48 divisors (see below), whose sum is σ = 19192320. Its totient is φ = 1739520.

The previous prime is 6688727. The next prime is 6688757. The reversal of 6688740 is 478866.

6688740 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1101 + ... + 3819.

It is an arithmetic number, because the mean of its divisors is an integer number (399840).

Almost surely, 2^6688740 is an apocalyptic number.

6688740 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6688740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (9596160).

6688740 is an abundant number, since it is smaller than the sum of its proper divisors (12503580).

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

6688740 is a wasteful number, since it uses less digits than its factorization.

6688740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2772 (or 2770 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 39.

The square root of 6688740 is about 2586.2598477338. The cubic root of 6688740 is about 188.4146949650.

The spelling of 6688740 in words is "six million, six hundred eighty-eight thousand, seven hundred forty".