320147521 has 2 divisors, whose sum is σ = 320147522. Its totient is φ = 320147520.

The previous prime is 320147483. The next prime is 320147537. The reversal of 320147521 is 125741023.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 304851600 + 15295921 = 17460^2 + 3911^2 .

It is a cyclic number.

It is not a de Polignac number, because 320147521 - 2¹¹ = 320145473 is a prime.

It is not a weakly prime, because it can be changed into another prime (320177521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160073760 + 160073761.

It is an arithmetic number, because the mean of its divisors is an integer number (160073761).

Almost surely, 2^320147521 is an apocalyptic number.

It is an amenable number.

320147521 is a deficient number, since it is larger than the sum of its proper divisors (1).

320147521 is an equidigital number, since it uses as much as digits as its factorization.

320147521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1680, while the sum is 25.

The square root of 320147521 is about 17892.6666821913. Note that the first 4 decimals coincide. The cubic root of 320147521 is about 684.0954697572.

Adding to 320147521 its reverse (125741023), we get a palindrome (445888544).

The spelling of 320147521 in words is "three hundred twenty million, one hundred forty-seven thousand, five hundred twenty-one".