6720340 has 36 divisors (see below), whose sum is σ = 15517908. Its totient is φ = 2442880.

The previous prime is 6720331. The next prime is 6720353. The reversal of 6720340 is 430276.

It can be written as a sum of positive squares in 2 ways, for example, as 1684804 + 5035536 = 1298^2 + 2244^2 .

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a congruent number.

It is an unprimeable 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 11 ways as a sum of consecutive naturals, for example, 1032 + ... + 3808.

It is an arithmetic number, because the mean of its divisors is an integer number (431053).

Almost surely, 2^6720340 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 6720340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7758954).

6720340 is an abundant number, since it is smaller than the sum of its proper divisors (8797568).

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

6720340 is a wasteful number, since it uses less digits than its factorization.

6720340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2808 (or 2795 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 22.

The square root of 6720340 is about 2592.3618574574. The cubic root of 6720340 is about 188.7109417303.

Subtracting from 6720340 its reverse (430276), we obtain a square (6290064 = 2508²).

The spelling of 6720340 in words is "six million, seven hundred twenty thousand, three hundred forty".