778440000000 has 640 divisors, whose sum is σ = 2797258464000. Its totient is φ = 191232000000.

The previous prime is 778439999999. The next prime is 778440000001. The reversal of 778440000000 is 44877.

It is an interprime number because it is at equal distance from previous prime (778439999999) and next prime (778440000001).

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 (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (778440000001) by changing a digit.

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 63 ways as a sum of consecutive naturals, for example, 1559999751 + ... + 1560000249.

It is an arithmetic number, because the mean of its divisors is an integer number (4370716350).

Almost surely, 2^778440000000 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 778440000000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1398629232000).

778440000000 is an abundant number, since it is smaller than the sum of its proper divisors (2018818464000).

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

778440000000 is an frugal number, since it uses more digits than its factorization.

778440000000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 568 (or 522 counting only the distinct ones).

The product of its (nonzero) digits is 6272, while the sum is 30.

Adding to 778440000000 its reverse (44877), we get a palindrome (778440044877).

The spelling of 778440000000 in words is "seven hundred seventy-eight billion, four hundred forty million", and thus it is an aban number.