6660843840 has 392 divisors, whose sum is σ = 27184746240. Its totient is φ = 1522105344.

The previous prime is 6660843779. The next prime is 6660843853. The reversal of 6660843840 is 483480666.

It is a Harshad number since it is a multiple of its sum of digits (45).

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 55 ways as a sum of consecutive naturals, for example, 1630921 + ... + 1634999.

Almost surely, 2^6660843840 is an apocalyptic number.

6660843840 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 6660843840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13592373120).

6660843840 is an abundant number, since it is smaller than the sum of its proper divisors (20523902400).

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

6660843840 is an equidigital number, since it uses as much as digits as its factorization.

6660843840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4121 (or 4096 counting only the distinct ones).

The product of its (nonzero) digits is 663552, while the sum is 45.

The square root of 6660843840 is about 81613.9929178814. The cubic root of 6660843840 is about 1881.5239491857.

The spelling of 6660843840 in words is "six billion, six hundred sixty million, eight hundred forty-three thousand, eight hundred forty".