778816 has 28 divisors (see below), whose sum is σ = 1586992. Its totient is φ = 379008.

The previous prime is 778793. The next prime is 778819. The reversal of 778816 is 618877.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (778819) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2611 + ... + 2893.

2⁷⁷⁸⁸¹⁶ 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 778816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (793496).

778816 is an abundant number, since it is smaller than the sum of its proper divisors (808176).

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

778816 is a wasteful number, since it uses less digits than its factorization.

778816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 338 (or 328 counting only the distinct ones).

The product of its digits is 18816, while the sum is 37.

The square root of 778816 is about 882.5055240620. The cubic root of 778816 is about 92.0050406816.

The spelling of 778816 in words is "seven hundred seventy-eight thousand, eight hundred sixteen".