1020521 has 4 divisors (see below), whose sum is σ = 1022544. Its totient is φ = 1018500.

The previous prime is 1020517. The next prime is 1020529. The reversal of 1020521 is 1250201.

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 1020521 - 2² = 1020517 is a prime.

It is a super-2 number, since 2×1020521² = 2082926222882, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1020529) 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, 446 + ... + 1496.

It is an arithmetic number, because the mean of its divisors is an integer number (255636).

2^1020521 is an apocalyptic number.

It is an amenable number.

1020521 is a deficient number, since it is larger than the sum of its proper divisors (2023).

1020521 is an equidigital number, since it uses as much as digits as its factorization.

1020521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2022.

The product of its (nonzero) digits is 20, while the sum is 11.

The square root of 1020521 is about 1010.2083943425. The cubic root of 1020521 is about 100.6794069417.

Adding to 1020521 its reverse (1250201), we get a palindrome (2270722).

The spelling of 1020521 in words is "one million, twenty thousand, five hundred twenty-one".