778961856 has 56 divisors (see below), whose sum is σ = 2108955904. Its totient is φ = 253612800.

The previous prime is 778961839. The next prime is 778961891. The reversal of 778961856 is 658169877.

It is a junction number, because it is equal to n+sod(n) for n = 778961796 and 778961805.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 38920 + ... + 55431.

Almost surely, 2^778961856 is an apocalyptic number.

It is an amenable number.

778961856 is an abundant number, since it is smaller than the sum of its proper divisors (1329994048).

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

778961856 is a wasteful number, since it uses less digits than its factorization.

778961856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94409 (or 94399 counting only the distinct ones).

The product of its digits is 5080320, while the sum is 57.

The square root of 778961856 is about 27909.8881402273. Note that the first 3 decimals coincide. The cubic root of 778961856 is about 920.1078386508.

The spelling of 778961856 in words is "seven hundred seventy-eight million, nine hundred sixty-one thousand, eight hundred fifty-six".