6445445857 has 2 divisors, whose sum is σ = 6445445858. Its totient is φ = 6445445856.

The previous prime is 6445445849. The next prime is 6445445863. The reversal of 6445445857 is 7585445446.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5176946401 + 1268499456 = 71951^2 + 35616^2 .

It is a cyclic number.

It is not a de Polignac number, because 6445445857 - 2³ = 6445445849 is a prime.

It is not a weakly prime, because it can be changed into another prime (6445475857) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3222722928 + 3222722929.

It is an arithmetic number, because the mean of its divisors is an integer number (3222722929).

Almost surely, 2^6445445857 is an apocalyptic number.

It is an amenable number.

6445445857 is a deficient number, since it is larger than the sum of its proper divisors (1).

6445445857 is an equidigital number, since it uses as much as digits as its factorization.

6445445857 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10752000, while the sum is 52.

The square root of 6445445857 is about 80283.5341586306. The cubic root of 6445445857 is about 1861.0197761837.

The spelling of 6445445857 in words is "six billion, four hundred forty-five million, four hundred forty-five thousand, eight hundred fifty-seven".