521101321 has 4 divisors (see below), whose sum is σ = 561186052. Its totient is φ = 481016592.

The previous prime is 521101291. The next prime is 521101327. The reversal of 521101321 is 123101125.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 22695696 + 498405625 = 4764^2 + 22325^2 .

It is a cyclic number.

It is not a de Polignac number, because 521101321 - 2¹⁹ = 520577033 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 521101295 and 521101304.

It is not an unprimeable number, because it can be changed into a prime (521101327) 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 3 ways as a sum of consecutive naturals, for example, 20042346 + ... + 20042371.

It is an arithmetic number, because the mean of its divisors is an integer number (140296513).

Almost surely, 2^521101321 is an apocalyptic number.

It is an amenable number.

521101321 is a deficient number, since it is larger than the sum of its proper divisors (40084731).

521101321 is a wasteful number, since it uses less digits than its factorization.

521101321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40084730.

The product of its (nonzero) digits is 60, while the sum is 16.

The square root of 521101321 is about 22827.6437899315. The cubic root of 521101321 is about 804.7124577757.

Adding to 521101321 its reverse (123101125), we get a palindrome (644202446).

The spelling of 521101321 in words is "five hundred twenty-one million, one hundred one thousand, three hundred twenty-one".