2149865 has 4 divisors (see below), whose sum is σ = 2579844. Its totient is φ = 1719888.

The previous prime is 2149859. The next prime is 2149867. The reversal of 2149865 is 5689412.

2149865 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1024144 + 1125721 = 1012^2 + 1061^2 .

It is a cyclic number.

It is not a de Polignac number, because 2149865 - 2¹² = 2145769 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2149867) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 214982 + ... + 214991.

It is an arithmetic number, because the mean of its divisors is an integer number (644961).

2^2149865 is an apocalyptic number.

It is an amenable number.

2149865 is a deficient number, since it is larger than the sum of its proper divisors (429979).

2149865 is an equidigital number, since it uses as much as digits as its factorization.

2149865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 429978.

The product of its digits is 17280, while the sum is 35.

The square root of 2149865 is about 1466.2417945209. The cubic root of 2149865 is about 129.0635866234.

The spelling of 2149865 in words is "two million, one hundred forty-nine thousand, eight hundred sixty-five".