328159921 has 2 divisors, whose sum is σ = 328159922. Its totient is φ = 328159920.

The previous prime is 328159889. The next prime is 328159973. The reversal of 328159921 is 129951823.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 281031696 + 47128225 = 16764^2 + 6865^2 .

It is an emirp because it is prime and its reverse (129951823) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 328159921 - 2⁵ = 328159889 is a prime.

It is not a weakly prime, because it can be changed into another prime (328159991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 164079960 + 164079961.

It is an arithmetic number, because the mean of its divisors is an integer number (164079961).

Almost surely, 2^328159921 is an apocalyptic number.

It is an amenable number.

328159921 is a deficient number, since it is larger than the sum of its proper divisors (1).

328159921 is an equidigital number, since it uses as much as digits as its factorization.

328159921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 38880, while the sum is 40.

The square root of 328159921 is about 18115.1848182678. The cubic root of 328159921 is about 689.7555116441.

The spelling of 328159921 in words is "three hundred twenty-eight million, one hundred fifty-nine thousand, nine hundred twenty-one".