778318577920 has 576 divisors, whose sum is σ = 2252994912000. Its totient is φ = 254492540928.

The previous prime is 778318577891. The next prime is 778318577941. The reversal of 778318577920 is 29775813877.

It is a super-2 number, since 2×778318577920² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (64).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 962074476 + ... + 962075284.

It is an arithmetic number, because the mean of its divisors is an integer number (3911449500).

Almost surely, 2^778318577920 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 778318577920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1126497456000).

778318577920 is an abundant number, since it is smaller than the sum of its proper divisors (1474676334080).

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

778318577920 is a wasteful number, since it uses less digits than its factorization.

778318577920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1058 (or 1044 counting only the distinct ones).

The product of its (nonzero) digits is 41489280, while the sum is 64.

The spelling of 778318577920 in words is "seven hundred seventy-eight billion, three hundred eighteen million, five hundred seventy-seven thousand, nine hundred twenty".