778643748 has 72 divisors (see below), whose sum is σ = 2063513088. Its totient is φ = 247091328.

The previous prime is 778643743. The next prime is 778643777. The reversal of 778643748 is 847346877.

It is a junction number, because it is equal to n+sod(n) for n = 778643694 and 778643703.

It is not an unprimeable number, because it can be changed into a prime (778643743) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 182536 + ... + 186752.

It is an arithmetic number, because the mean of its divisors is an integer number (28659904).

Almost surely, 2^778643748 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 778643748, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1031756544).

778643748 is an abundant number, since it is smaller than the sum of its proper divisors (1284869340).

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

778643748 is a wasteful number, since it uses less digits than its factorization.

778643748 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4473 (or 4468 counting only the distinct ones).

The product of its digits is 6322176, while the sum is 54.

The square root of 778643748 is about 27904.1887178251. The cubic root of 778643748 is about 919.9825721336.

The spelling of 778643748 in words is "seven hundred seventy-eight million, six hundred forty-three thousand, seven hundred forty-eight".