778626651968 has 70 divisors (see below), whose sum is σ = 1699587480930. Its totient is φ = 353920779520.

The previous prime is 778626651889. The next prime is 778626652007. The reversal of 778626651968 is 869156626877.

It can be written as a sum of positive squares in only one way, i.e., 715770145024 + 62856506944 = 846032^2 + 250712^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 521546 + ... + 1352502.

Almost surely, 2^778626651968 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 778626651968, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (849793740465).

778626651968 is an abundant number, since it is smaller than the sum of its proper divisors (920960828962).

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

778626651968 is an frugal number, since it uses more digits than its factorization.

778626651968 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 831013 (or 830970 counting only the distinct ones).

The product of its digits is 365783040, while the sum is 71.

The spelling of 778626651968 in words is "seven hundred seventy-eight billion, six hundred twenty-six million, six hundred fifty-one thousand, nine hundred sixty-eight".