3865645 has 16 divisors (see below), whose sum is σ = 5581440. Its totient is φ = 2510784.

The previous prime is 3865637. The next prime is 3865663. The reversal of 3865645 is 5465683.

It is a cyclic number.

It is not a de Polignac number, because 3865645 - 2³ = 3865637 is a prime.

It is a super-3 number, since 3×3865645³ (a number of 21 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2242 + ... + 3571.

It is an arithmetic number, because the mean of its divisors is an integer number (348840).

Almost surely, 2^3865645 is an apocalyptic number.

3865645 is a gapful number since it is divisible by the number (35) formed by its first and last digit.

It is an amenable number.

3865645 is a deficient number, since it is larger than the sum of its proper divisors (1715795).

3865645 is a wasteful number, since it uses less digits than its factorization.

3865645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5844.

The product of its digits is 86400, while the sum is 37.

The square root of 3865645 is about 1966.1243602580. The cubic root of 3865645 is about 156.9425324178.

The spelling of 3865645 in words is "three million, eight hundred sixty-five thousand, six hundred forty-five".