2165859 has 14 divisors (see below), whose sum is σ = 3248396. Its totient is φ = 1443420.

The previous prime is 2165857. The next prime is 2165873. The reversal of 2165859 is 9585612.

It is a happy number.

It is not a de Polignac number, because 2165859 - 2¹ = 2165857 is a prime.

It is an Ulam number.

It is a Duffinian number.

2165859 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (2165857) by changing a digit.

It is a polite number, since it can be written in 13 ways as a sum of consecutive naturals, for example, 757 + ... + 2214.

2^2165859 is an apocalyptic number.

2165859 is a deficient number, since it is larger than the sum of its proper divisors (1082537).

2165859 is an frugal number, since it uses more digits than its factorization.

2165859 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2989 (or 2974 counting only the distinct ones).

The product of its digits is 21600, while the sum is 36.

The square root of 2165859 is about 1471.6857680905. The cubic root of 2165859 is about 129.3828539655.

The spelling of 2165859 in words is "two million, one hundred sixty-five thousand, eight hundred fifty-nine".