320540521 has 4 divisors (see below), whose sum is σ = 366332032. Its totient is φ = 274749012.

The previous prime is 320540513. The next prime is 320540537. The reversal of 320540521 is 125045023.

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, and also an emirpimes, since its reverse is a distinct semiprime: 125045023 = 19 ⋅6581317.

It is a cyclic number.

It is not a de Polignac number, because 320540521 - 2³ = 320540513 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 320540492 and 320540501.

It is not an unprimeable number, because it can be changed into a prime (320540821) 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, 22895745 + ... + 22895758.

It is an arithmetic number, because the mean of its divisors is an integer number (91583008).

Almost surely, 2^320540521 is an apocalyptic number.

It is an amenable number.

320540521 is a deficient number, since it is larger than the sum of its proper divisors (45791511).

320540521 is an equidigital number, since it uses as much as digits as its factorization.

320540521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45791510.

The product of its (nonzero) digits is 1200, while the sum is 22.

The square root of 320540521 is about 17903.6454667758. The cubic root of 320540521 is about 684.3752778326.

Adding to 320540521 its reverse (125045023), we get a palindrome (445585544).

The spelling of 320540521 in words is "three hundred twenty million, five hundred forty thousand, five hundred twenty-one".