3943805 has 4 divisors (see below), whose sum is σ = 4732572. Its totient is φ = 3155040.

The previous prime is 3943799. The next prime is 3943829. The reversal of 3943805 is 5083493.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5083493 = 17 ⋅299029.

It can be written as a sum of positive squares in 2 ways, for example, as 1006009 + 2937796 = 1003^2 + 1714^2 .

It is not a de Polignac number, because 3943805 - 2¹⁰ = 3942781 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 394376 + ... + 394385.

It is an arithmetic number, because the mean of its divisors is an integer number (1183143).

Almost surely, 2^3943805 is an apocalyptic number.

It is an amenable number.

3943805 is a deficient number, since it is larger than the sum of its proper divisors (788767).

3943805 is an equidigital number, since it uses as much as digits as its factorization.

3943805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 788766.

The product of its (nonzero) digits is 12960, while the sum is 32.

The square root of 3943805 is about 1985.9015584867. The cubic root of 3943805 is about 157.9932299615.

The spelling of 3943805 in words is "three million, nine hundred forty-three thousand, eight hundred five".