6857081789 has 2 divisors, whose sum is σ = 6857081790. Its totient is φ = 6857081788.

The previous prime is 6857081783. The next prime is 6857081831. The reversal of 6857081789 is 9871807586.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 4629713764 + 2227368025 = 68042^2 + 47195^2 .

It is a cyclic number.

It is not a de Polignac number, because 6857081789 - 2³² = 2562114493 is a prime.

It is a super-2 number, since 2×6857081789² = 94039141322070881042, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6857081783) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3428540894 + 3428540895.

It is an arithmetic number, because the mean of its divisors is an integer number (3428540895).

Almost surely, 2^6857081789 is an apocalyptic number.

It is an amenable number.

6857081789 is a deficient number, since it is larger than the sum of its proper divisors (1).

6857081789 is an equidigital number, since it uses as much as digits as its factorization.

6857081789 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6773760, while the sum is 59.

The square root of 6857081789 is about 82807.4983863176. The cubic root of 6857081789 is about 1899.8228633568.

The spelling of 6857081789 in words is "six billion, eight hundred fifty-seven million, eighty-one thousand, seven hundred eighty-nine".