3821521 has 4 divisors (see below), whose sum is σ = 4168944. Its totient is φ = 3474100.

The previous prime is 3821513. The next prime is 3821563. The reversal of 3821521 is 1251283.

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.

It is a cyclic number.

It is not a de Polignac number, because 3821521 - 2³ = 3821513 is a prime.

It is a Smith number, since the sum of its digits (22) 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.

It is a junction number, because it is equal to n+sod(n) for n = 3821492 and 3821501.

It is not an unprimeable number, because it can be changed into a prime (3821581) by changing a digit.

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, 173695 + ... + 173716.

It is an arithmetic number, because the mean of its divisors is an integer number (1042236).

Almost surely, 2^3821521 is an apocalyptic number.

It is an amenable number.

3821521 is a deficient number, since it is larger than the sum of its proper divisors (347423).

3821521 is a wasteful number, since it uses less digits than its factorization.

3821521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 347422.

The product of its digits is 480, while the sum is 22.

The square root of 3821521 is about 1954.8710954945. The cubic root of 3821521 is about 156.3431112229.

The spelling of 3821521 in words is "three million, eight hundred twenty-one thousand, five hundred twenty-one".