778703648 has 18 divisors (see below), whose sum is σ = 1533383649. Its totient is φ = 389272896.

The previous prime is 778703599. The next prime is 778703677. The reversal of 778703648 is 846307877.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in 2 ways, for example, as 750102544 + 28601104 = 27388^2 + 5348^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=19732.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 778703596 and 778703605.

It is an unprimeable number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 155390 + ... + 160322.

Almost surely, 2^778703648 is an apocalyptic number.

It is an amenable number.

778703648 is a deficient number, since it is larger than the sum of its proper divisors (754680001).

778703648 is an frugal number, since it uses more digits than its factorization.

778703648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9876 (or 4935 counting only the distinct ones).

The product of its (nonzero) digits is 1580544, while the sum is 50.

The square root of 778703648 is about 27905.2620127459. The cubic root of 778703648 is about 920.0061625296.

Multiplying 778703648 by its sum of digits (50), we get a square (38935182400 = 197320²).

It can be divided in two parts, 77870 and 3648, that added together give a palindrome (81518).

The spelling of 778703648 in words is "seven hundred seventy-eight million, seven hundred three thousand, six hundred forty-eight".