778028161 has 2 divisors, whose sum is σ = 778028162. Its totient is φ = 778028160.

The previous prime is 778028123. The next prime is 778028189. The reversal of 778028161 is 161820877.

778028161 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 769507600 + 8520561 = 27740^2 + 2919^2 .

It is a cyclic number.

It is not a de Polignac number, because 778028161 - 2¹⁹ = 777503873 is a prime.

It is not a weakly prime, because it can be changed into another prime (778028191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 389014080 + 389014081.

It is an arithmetic number, because the mean of its divisors is an integer number (389014081).

Almost surely, 2^778028161 is an apocalyptic number.

It is an amenable number.

778028161 is a deficient number, since it is larger than the sum of its proper divisors (1).

778028161 is an equidigital number, since it uses as much as digits as its factorization.

778028161 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 37632, while the sum is 40.

The square root of 778028161 is about 27893.1561677771. The cubic root of 778028161 is about 919.7400655859.

The spelling of 778028161 in words is "seven hundred seventy-eight million, twenty-eight thousand, one hundred sixty-one".