3865861 has 4 divisors (see below), whose sum is σ = 3918892. Its totient is φ = 3812832.

The previous prime is 3865859. The next prime is 3865867. The reversal of 3865861 is 1685683.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 820836 + 3045025 = 906^2 + 1745^2 .

It is a cyclic number.

It is not a de Polignac number, because 3865861 - 2¹ = 3865859 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 3865861.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3865867) 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, 26406 + ... + 26551.

It is an arithmetic number, because the mean of its divisors is an integer number (979723).

Almost surely, 2^3865861 is an apocalyptic number.

It is an amenable number.

3865861 is a deficient number, since it is larger than the sum of its proper divisors (53031).

3865861 is an equidigital number, since it uses as much as digits as its factorization.

3865861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53030.

The product of its digits is 34560, while the sum is 37.

The square root of 3865861 is about 1966.1792898919. The cubic root of 3865861 is about 156.9454555139.

The spelling of 3865861 in words is "three million, eight hundred sixty-five thousand, eight hundred sixty-one".