3865509 has 16 divisors (see below), whose sum is σ = 5823040. Its totient is φ = 2533680.

The previous prime is 3865481. The next prime is 3865513. The reversal of 3865509 is 9055683.

It is not a de Polignac number, because 3865509 - 2¹² = 3861413 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3865529) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 474 + ... + 2820.

It is an arithmetic number, because the mean of its divisors is an integer number (363940).

Almost surely, 2^3865509 is an apocalyptic number.

It is an amenable number.

3865509 is a deficient number, since it is larger than the sum of its proper divisors (1957531).

3865509 is a wasteful number, since it uses less digits than its factorization.

3865509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2417 (or 2411 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 36.

The square root of 3865509 is about 1966.0897741456. The cubic root of 3865509 is about 156.9406918940.

The spelling of 3865509 in words is "three million, eight hundred sixty-five thousand, five hundred nine".