8201521 has 4 divisors (see below), whose sum is σ = 8633200. Its totient is φ = 7769844.

The previous prime is 8201513. The next prime is 8201527. The reversal of 8201521 is 1251028.

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 8201521 - 2³ = 8201513 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19), and also a Moran number because the ratio is a prime number: 431659 = 8201521 / (8 + 2 + 0 + 1 + 5 + 2 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8201527) 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, 215811 + ... + 215848.

It is an arithmetic number, because the mean of its divisors is an integer number (2158300).

Almost surely, 2^8201521 is an apocalyptic number.

It is an amenable number.

8201521 is a deficient number, since it is larger than the sum of its proper divisors (431679).

8201521 is a wasteful number, since it uses less digits than its factorization.

8201521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 431678.

The product of its (nonzero) digits is 160, while the sum is 19.

The square root of 8201521 is about 2863.8297784610. The cubic root of 8201521 is about 201.6654348064.

Adding to 8201521 its reverse (1251028), we get a palindrome (9452549).

The spelling of 8201521 in words is "eight million, two hundred one thousand, five hundred twenty-one".