320535221 has 4 divisors (see below), whose sum is σ = 339390252. Its totient is φ = 301680192.

The previous prime is 320535203. The next prime is 320535223. The reversal of 320535221 is 122535023.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 122535023 = 13 ⋅9425771.

It can be written as a sum of positive squares in 2 ways, for example, as 121330225 + 199204996 = 11015^2 + 14114^2 .

It is a cyclic number.

It is not a de Polignac number, because 320535221 - 2⁶ = 320535157 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (320535223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9427490 + ... + 9427523.

It is an arithmetic number, because the mean of its divisors is an integer number (84847563).

Almost surely, 2^320535221 is an apocalyptic number.

It is an amenable number.

320535221 is a deficient number, since it is larger than the sum of its proper divisors (18855031).

320535221 is a wasteful number, since it uses less digits than its factorization.

320535221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18855030.

The product of its (nonzero) digits is 1800, while the sum is 23.

The square root of 320535221 is about 17903.4974516154. The cubic root of 320535221 is about 684.3715058612.

The spelling of 320535221 in words is "three hundred twenty million, five hundred thirty-five thousand, two hundred twenty-one".