1021521 has 8 divisors (see below), whose sum is σ = 1371040. Its totient is φ = 676512.

The previous prime is 1021487. The next prime is 1021541. The reversal of 1021521 is 1251201.

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

It is not a de Polignac number, because 1021521 - 2⁶ = 1021457 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 16.

It is a junction number, because it is equal to n+sod(n) for n = 1021497 and 1021506.

It is not an unprimeable number, because it can be changed into a prime (1021541) 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 7 ways as a sum of consecutive naturals, for example, 556 + ... + 1533.

It is an arithmetic number, because the mean of its divisors is an integer number (171380).

2^1021521 is an apocalyptic number.

It is an amenable number.

1021521 is a deficient number, since it is larger than the sum of its proper divisors (349519).

1021521 is a wasteful number, since it uses less digits than its factorization.

1021521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2255.

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

The square root of 1021521 is about 1010.7032205351. The cubic root of 1021521 is about 100.7122811762.

Adding to 1021521 its reverse (1251201), we get a palindrome (2272722).

The spelling of 1021521 in words is "one million, twenty-one thousand, five hundred twenty-one".