3996805 has 4 divisors (see below), whose sum is σ = 4796172. Its totient is φ = 3197440.

The previous prime is 3996793. The next prime is 3996827. The reversal of 3996805 is 5086993.

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 1940449 + 2056356 = 1393^2 + 1434^2 .

It is not a de Polignac number, because 3996805 - 2¹⁷ = 3865733 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

3996805 is a lucky number.

It is a congruent number.

It is an unprimeable number.

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, 399676 + ... + 399685.

It is an arithmetic number, because the mean of its divisors is an integer number (1199043).

Almost surely, 2^3996805 is an apocalyptic number.

It is an amenable number.

3996805 is a deficient number, since it is larger than the sum of its proper divisors (799367).

3996805 is an equidigital number, since it uses as much as digits as its factorization.

3996805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 799366.

The product of its (nonzero) digits is 58320, while the sum is 40.

The square root of 3996805 is about 1999.2010904359. The cubic root of 3996805 is about 158.6978293859.

The spelling of 3996805 in words is "three million, nine hundred ninety-six thousand, eight hundred five".