778085280 has 144 divisors (see below), whose sum is σ = 3034571904. Its totient is φ = 177845760.

The previous prime is 778085279. The next prime is 778085303. The reversal of 778085280 is 82580877.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 28516 + ... + 48675.

It is an arithmetic number, because the mean of its divisors is an integer number (21073416).

Almost surely, 2^778085280 is an apocalyptic number.

778085280 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

778085280 is an abundant number, since it is smaller than the sum of its proper divisors (2256486624).

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

778085280 is a wasteful number, since it uses less digits than its factorization.

778085280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77219 (or 77208 counting only the distinct ones).

The product of its (nonzero) digits is 250880, while the sum is 45.

The square root of 778085280 is about 27894.1800381370. The cubic root of 778085280 is about 919.7625726321.

The spelling of 778085280 in words is "seven hundred seventy-eight million, eighty-five thousand, two hundred eighty".