3865506 has 16 divisors (see below), whose sum is σ = 7750848. Its totient is φ = 1285200.

The previous prime is 3865481. The next prime is 3865513. The reversal of 3865506 is 6055683.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3276 + ... + 4296.

It is an arithmetic number, because the mean of its divisors is an integer number (484428).

Almost surely, 2^3865506 is an apocalyptic number.

3865506 is an abundant number, since it is smaller than the sum of its proper divisors (3885342).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

3865506 is a wasteful number, since it uses less digits than its factorization.

3865506 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1657.

The product of its (nonzero) digits is 21600, while the sum is 33.

The square root of 3865506 is about 1966.0890112098. The cubic root of 3865506 is about 156.9406512938.

It can be divided in two parts, 3865 and 506, that added together give a triangular number (4371 = T₉₃).

The spelling of 3865506 in words is "three million, eight hundred sixty-five thousand, five hundred six".