328032721 has 2 divisors, whose sum is σ = 328032722. Its totient is φ = 328032720.

The previous prime is 328032707. The next prime is 328032769. The reversal of 328032721 is 127230823.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 319122496 + 8910225 = 17864^2 + 2985^2 .

It is a cyclic number.

It is not a de Polignac number, because 328032721 - 2⁹ = 328032209 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 328032721.

It is not a weakly prime, because it can be changed into another prime (328032781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 164016360 + 164016361.

It is an arithmetic number, because the mean of its divisors is an integer number (164016361).

Almost surely, 2^328032721 is an apocalyptic number.

It is an amenable number.

328032721 is a deficient number, since it is larger than the sum of its proper divisors (1).

328032721 is an equidigital number, since it uses as much as digits as its factorization.

328032721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4032, while the sum is 28.

The square root of 328032721 is about 18111.6736112376. The cubic root of 328032721 is about 689.6663800612. Note that the first 3 decimals are identical.

The spelling of 328032721 in words is "three hundred twenty-eight million, thirty-two thousand, seven hundred twenty-one".