6840840 has 64 divisors (see below), whose sum is σ = 20750400. Its totient is φ = 1804032.

The previous prime is 6840811. The next prime is 6840857. The reversal of 6840840 is 480486.

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 6840798 and 6840807.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12819 + ... + 13341.

It is an arithmetic number, because the mean of its divisors is an integer number (324225).

Almost surely, 2^6840840 is an apocalyptic number.

6840840 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is a pronic number, being equal to 2615×2616.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6840840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10375200).

6840840 is an abundant number, since it is smaller than the sum of its proper divisors (13909560).

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

6840840 is a wasteful number, since it uses less digits than its factorization.

6840840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 646 (or 642 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 30.

The square root of 6840840 is about 2615.4999522080. The cubic root of 6840840 is about 189.8321694320.

The spelling of 6840840 in words is "six million, eight hundred forty thousand, eight hundred forty".