6328721857 has 2 divisors, whose sum is σ = 6328721858. Its totient is φ = 6328721856.

The previous prime is 6328721851. The next prime is 6328721873. The reversal of 6328721857 is 7581278236.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6304995216 + 23726641 = 79404^2 + 4871^2 .

It is a cyclic number.

It is not a de Polignac number, because 6328721857 - 2¹⁹ = 6328197569 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 6328721857.

It is not a weakly prime, because it can be changed into another prime (6328721851) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3164360928 + 3164360929.

It is an arithmetic number, because the mean of its divisors is an integer number (3164360929).

Almost surely, 2^6328721857 is an apocalyptic number.

It is an amenable number.

6328721857 is a deficient number, since it is larger than the sum of its proper divisors (1).

6328721857 is an equidigital number, since it uses as much as digits as its factorization.

6328721857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1128960, while the sum is 49.

The square root of 6328721857 is about 79553.2642762068. The cubic root of 6328721857 is about 1849.7172060556.

The spelling of 6328721857 in words is "six billion, three hundred twenty-eight million, seven hundred twenty-one thousand, eight hundred fifty-seven".