2165857 has 2 divisors, whose sum is σ = 2165858. Its totient is φ = 2165856.

The previous prime is 2165843. The next prime is 2165873. The reversal of 2165857 is 7585612.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2005056 + 160801 = 1416^2 + 401^2 .

It is a cyclic number.

It is not a de Polignac number, because 2165857 - 2¹¹ = 2163809 is a prime.

It is a super-3 number, since 3×2165857³ = 30479693254052033379, which contains 333 as substring.

2165857 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (2165897) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1082928 + 1082929.

It is an arithmetic number, because the mean of its divisors is an integer number (1082929).

2^2165857 is an apocalyptic number.

It is an amenable number.

2165857 is a deficient number, since it is larger than the sum of its proper divisors (1).

2165857 is an equidigital number, since it uses as much as digits as its factorization.

2165857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 16800, while the sum is 34.

The square root of 2165857 is about 1471.6850885974. The cubic root of 2165857 is about 129.3828141406.

The spelling of 2165857 in words is "two million, one hundred sixty-five thousand, eight hundred fifty-seven".