6821340 has 48 divisors (see below), whose sum is σ = 19934208. Its totient is φ = 1739584.

The previous prime is 6821303. The next prime is 6821383. The reversal of 6821340 is 431286.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 6821340.

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 15 ways as a sum of consecutive naturals, for example, 1092 + ... + 3851.

It is an arithmetic number, because the mean of its divisors is an integer number (415296).

Almost surely, 2^6821340 is an apocalyptic number.

6821340 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

6821340 is an abundant number, since it is smaller than the sum of its proper divisors (13112868).

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

6821340 is a wasteful number, since it uses less digits than its factorization.

6821340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4978 (or 4976 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 24.

The square root of 6821340 is about 2611.7695150989. The cubic root of 6821340 is about 189.6516238568.

The spelling of 6821340 in words is "six million, eight hundred twenty-one thousand, three hundred forty".