320649128 has 8 divisors (see below), whose sum is σ = 601217130. Its totient is φ = 160324560.

The previous prime is 320649113. The next prime is 320649157. The reversal of 320649128 is 821946023.

It can be written as a sum of positive squares in only one way, i.e., 303526084 + 17123044 = 17422^2 + 4138^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20040563 + ... + 20040578.

Almost surely, 2^320649128 is an apocalyptic number.

It is an amenable number.

320649128 is a deficient number, since it is larger than the sum of its proper divisors (280568002).

320649128 is a wasteful number, since it uses less digits than its factorization.

320649128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40081147 (or 40081143 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 35.

The square root of 320649128 is about 17906.6783072685. The cubic root of 320649128 is about 684.4525634879.

The spelling of 320649128 in words is "three hundred twenty million, six hundred forty-nine thousand, one hundred twenty-eight".