778313873 has 4 divisors (see below), whose sum is σ = 824097060. Its totient is φ = 732530688.

The previous prime is 778313849. The next prime is 778313911. The reversal of 778313873 is 378313877.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 554272849 + 224041024 = 23543^2 + 14968^2 .

It is a cyclic number.

It is not a de Polignac number, because 778313873 - 2⁸ = 778313617 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (778315873) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22891568 + ... + 22891601.

It is an arithmetic number, because the mean of its divisors is an integer number (206024265).

Almost surely, 2^778313873 is an apocalyptic number.

It is an amenable number.

778313873 is a deficient number, since it is larger than the sum of its proper divisors (45783187).

778313873 is a wasteful number, since it uses less digits than its factorization.

778313873 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45783186.

The product of its digits is 592704, while the sum is 47.

The square root of 778313873 is about 27898.2772407186. The cubic root of 778313873 is about 919.8526358958.

The spelling of 778313873 in words is "seven hundred seventy-eight million, three hundred thirteen thousand, eight hundred seventy-three".