3809521 has 4 divisors (see below), whose sum is σ = 3845232. Its totient is φ = 3773812.

The previous prime is 3809503. The next prime is 3809539. The reversal of 3809521 is 1259083.

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 an interprime number because it is at equal distance from previous prime (3809503) and next prime (3809539).

It is a cyclic number.

It is not a de Polignac number, because 3809521 - 2⁵ = 3809489 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 3809521.

It is not an unprimeable number, because it can be changed into a prime (3809501) 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, 17695 + ... + 17908.

It is an arithmetic number, because the mean of its divisors is an integer number (961308).

Almost surely, 2^3809521 is an apocalyptic number.

It is an amenable number.

3809521 is a deficient number, since it is larger than the sum of its proper divisors (35711).

3809521 is a wasteful number, since it uses less digits than its factorization.

3809521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35710.

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

The square root of 3809521 is about 1951.7994261706. The cubic root of 3809521 is about 156.1792947297.

The spelling of 3809521 in words is "three million, eight hundred nine thousand, five hundred twenty-one".