3865409 has 4 divisors (see below), whose sum is σ = 4092804. Its totient is φ = 3638016.

The previous prime is 3865363. The next prime is 3865429. The reversal of 3865409 is 9045683.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9045683 = 17 ⋅532099.

It can be written as a sum of positive squares in 2 ways, for example, as 2310400 + 1555009 = 1520^2 + 1247^2 .

It is a cyclic number.

It is not a de Polignac number, because 3865409 - 2⁸ = 3865153 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (3865429) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 113672 + ... + 113705.

It is an arithmetic number, because the mean of its divisors is an integer number (1023201).

Almost surely, 2^3865409 is an apocalyptic number.

It is an amenable number.

3865409 is a deficient number, since it is larger than the sum of its proper divisors (227395).

3865409 is a wasteful number, since it uses less digits than its factorization.

3865409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 227394.

The product of its (nonzero) digits is 25920, while the sum is 35.

The square root of 3865409 is about 1966.0643427925. The cubic root of 3865409 is about 156.9393385402.

The spelling of 3865409 in words is "three million, eight hundred sixty-five thousand, four hundred nine".