6778347649920 has 640 divisors, whose sum is σ = 30179803737600. Its totient is φ = 1408486993920.

The previous prime is 6778347649891. The next prime is 6778347649991. The reversal of 6778347649920 is 299467438776.

It is a happy number.

6778347649920 is a `hidden beast` number, since 6 + 7 + 78 + 3 + 47 + 6 + 499 + 20 = 666.

It is a tau number, because it is divible by the number of its divisors (640).

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 3142621 + ... + 4840739.

It is an arithmetic number, because the mean of its divisors is an integer number (47155943340).

Almost surely, 2^{6778347649920} is an apocalyptic number.

6778347649920 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 6778347649920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15089901868800).

6778347649920 is an abundant number, since it is smaller than the sum of its proper divisors (23401456087680).

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

6778347649920 is a wasteful number, since it uses less digits than its factorization.

6778347649920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1698168 (or 1698147 counting only the distinct ones).

The product of its (nonzero) digits is 768144384, while the sum is 72.

The spelling of 6778347649920 in words is "six trillion, seven hundred seventy-eight billion, three hundred forty-seven million, six hundred forty-nine thousand, nine hundred twenty".