3805921 has 4 divisors (see below), whose sum is σ = 4349632. Its totient is φ = 3262212.

The previous prime is 3805903. The next prime is 3805927. The reversal of 3805921 is 1295083.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1295083 = 617 ⋅2099.

It is a cyclic number.

It is not a de Polignac number, because 3805921 - 2⁵ = 3805889 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 3805921.

It is not an unprimeable number, because it can be changed into a prime (3805927) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 271845 + ... + 271858.

It is an arithmetic number, because the mean of its divisors is an integer number (1087408).

Almost surely, 2^3805921 is an apocalyptic number.

It is an amenable number.

3805921 is a deficient number, since it is larger than the sum of its proper divisors (543711).

3805921 is an equidigital number, since it uses as much as digits as its factorization.

3805921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 543710.

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 3805921 is about 1950.8769822826. The cubic root of 3805921 is about 156.1300827105.

The spelling of 3805921 in words is "three million, eight hundred five thousand, nine hundred twenty-one".