3943809 has 20 divisors (see below), whose sum is σ = 5945940. Its totient is φ = 2604960.

The previous prime is 3943799. The next prime is 3943829. The reversal of 3943809 is 9083493.

It can be written as a sum of positive squares in 2 ways, for example, as 129600 + 3814209 = 360^2 + 1953^2 .

It is not a de Polignac number, because 3943809 - 2⁵ = 3943777 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3943829) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 14527 + ... + 14795.

It is an arithmetic number, because the mean of its divisors is an integer number (297297).

Almost surely, 2^3943809 is an apocalyptic number.

It is an amenable number.

3943809 is a deficient number, since it is larger than the sum of its proper divisors (2002131).

3943809 is a wasteful number, since it uses less digits than its factorization.

3943809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 462 (or 453 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 36.

The square root of 3943809 is about 1985.9025655857. The cubic root of 3943809 is about 157.9932833763.

The spelling of 3943809 in words is "three million, nine hundred forty-three thousand, eight hundred nine".