6884640 has 144 divisors (see below), whose sum is σ = 26889408. Its totient is φ = 1571328.

The previous prime is 6884639. The next prime is 6884641. The reversal of 6884640 is 464886.

6884640 is a `hidden beast` number, since 6 + 8 + 8 + 4 + 640 = 666.

It is an interprime number because it is at equal distance from previous prime (6884639) and next prime (6884641).

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 6884595 and 6884604.

It is not an unprimeable number, because it can be changed into a prime (6884641) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9739 + ... + 10421.

It is an arithmetic number, because the mean of its divisors is an integer number (186732).

Almost surely, 2^6884640 is an apocalyptic number.

6884640 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 6884640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13444704).

6884640 is an abundant number, since it is smaller than the sum of its proper divisors (20004768).

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

6884640 is a wasteful number, since it uses less digits than its factorization.

6884640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 711 (or 700 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 36.

The square root of 6884640 is about 2623.8597523496. The cubic root of 6884640 is about 190.2364553779.

It can be divided in two parts, 68846 and 40, that added together give a palindrome (68886).

The spelling of 6884640 in words is "six million, eight hundred eighty-four thousand, six hundred forty".