10021521 has 4 divisors (see below), whose sum is σ = 13362032. Its totient is φ = 6681012.

The previous prime is 10021519. The next prime is 10021541. The reversal of 10021521 is 12512001.

10021521 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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 not a de Polignac number, because 10021521 - 2¹ = 10021519 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 10021497 and 10021506.

It is not an unprimeable number, because it can be changed into a prime (10021511) 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 in 3 ways as a sum of consecutive naturals, for example, 1670251 + ... + 1670256.

It is an arithmetic number, because the mean of its divisors is an integer number (3340508).

Almost surely, 2^10021521 is an apocalyptic number.

It is an amenable number.

10021521 is a deficient number, since it is larger than the sum of its proper divisors (3340511).

10021521 is an equidigital number, since it uses as much as digits as its factorization.

10021521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3340510.

The product of its (nonzero) digits is 20, while the sum is 12.

The square root of 10021521 is about 3165.6786002372. The cubic root of 10021521 is about 215.5979102283.

Adding to 10021521 its reverse (12512001), we get a palindrome (22533522).

The spelling of 10021521 in words is "ten million, twenty-one thousand, five hundred twenty-one".