3805621 has 2 divisors, whose sum is σ = 3805622. Its totient is φ = 3805620.

The previous prime is 3805573. The next prime is 3805639. The reversal of 3805621 is 1265083.

It is a happy number.

3805621 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2436721 + 1368900 = 1561^2 + 1170^2 .

It is an emirp because it is prime and its reverse (1265083) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 3805621 - 2¹³ = 3797429 is a prime.

3805621 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3805121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1902810 + 1902811.

It is an arithmetic number, because the mean of its divisors is an integer number (1902811).

Almost surely, 2^3805621 is an apocalyptic number.

It is an amenable number.

3805621 is a deficient number, since it is larger than the sum of its proper divisors (1).

3805621 is an equidigital number, since it uses as much as digits as its factorization.

3805621 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1440, while the sum is 25.

The square root of 3805621 is about 1950.8000922698. The cubic root of 3805621 is about 156.1259803084.

The spelling of 3805621 in words is "three million, eight hundred five thousand, six hundred twenty-one".