778220 has 24 divisors (see below), whose sum is σ = 1651104. Its totient is φ = 308096.

The previous prime is 778213. The next prime is 778223. The reversal of 778220 is 22877.

It is a self number, because there is not a number n which added to its sum of digits gives 778220.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 778220.

It is not an unprimeable number, because it can be changed into a prime (778223) by changing a digit.

778220 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3224 + ... + 3456.

It is an arithmetic number, because the mean of its divisors is an integer number (68796).

2⁷⁷⁸²²⁰ is an apocalyptic number.

It is an amenable number.

778220 is an abundant number, since it is smaller than the sum of its proper divisors (872884).

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

778220 is a wasteful number, since it uses less digits than its factorization.

778220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 409 (or 407 counting only the distinct ones).

The product of its (nonzero) digits is 1568, while the sum is 26.

The square root of 778220 is about 882.1677844945. The cubic root of 778220 is about 91.9815653045.

The spelling of 778220 in words is "seven hundred seventy-eight thousand, two hundred twenty".