3866665 has 16 divisors (see below), whose sum is σ = 5100480. Its totient is φ = 2790720.

The previous prime is 3866651. The next prime is 3866713. The reversal of 3866665 is 5666683.

It is not a de Polignac number, because 3866665 - 2¹⁵ = 3833897 is a prime.

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, 12442 + ... + 12748.

It is an arithmetic number, because the mean of its divisors is an integer number (318780).

Almost surely, 2^3866665 is an apocalyptic number.

It is an amenable number.

3866665 is a deficient number, since it is larger than the sum of its proper divisors (1233815).

3866665 is a wasteful number, since it uses less digits than its factorization.

3866665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 552.

The product of its digits is 155520, while the sum is 40.

The square root of 3866665 is about 1966.3837367106. The cubic root of 3866665 is about 156.9563349704.

It can be divided in two parts, 3 and 866665, that added together give a palindrome (866668).

The spelling of 3866665 in words is "three million, eight hundred sixty-six thousand, six hundred sixty-five".