8204521 has 8 divisors (see below), whose sum is σ = 8861384. Its totient is φ = 7551360.

The previous prime is 8204513. The next prime is 8204527. The reversal of 8204521 is 1254028.

It can be written as a sum of positive squares in 4 ways, for example, as 1123600 + 7080921 = 1060^2 + 2661^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 8204521 - 2³ = 8204513 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 8204492 and 8204501.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8204527) 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 7 ways as a sum of consecutive naturals, for example, 5251 + ... + 6631.

It is an arithmetic number, because the mean of its divisors is an integer number (1107673).

Almost surely, 2^8204521 is an apocalyptic number.

It is an amenable number.

8204521 is a deficient number, since it is larger than the sum of its proper divisors (656863).

8204521 is a wasteful number, since it uses less digits than its factorization.

8204521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1851.

The product of its (nonzero) digits is 640, while the sum is 22.

The square root of 8204521 is about 2864.3535047197. The cubic root of 8204521 is about 201.6900205938.

Adding to 8204521 its reverse (1254028), we get a palindrome (9458549).

The spelling of 8204521 in words is "eight million, two hundred four thousand, five hundred twenty-one".