5128690664 has 8 divisors (see below), whose sum is σ = 9616295010. Its totient is φ = 2564345328.

The previous prime is 5128690663. The next prime is 5128690681. The reversal of 5128690664 is 4660968215.

It can be written as a sum of positive squares in only one way, i.e., 5118257764 + 10432900 = 71542^2 + 3230^2 .

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

It is not an unprimeable number, because it can be changed into a prime (5128690663) 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 as a sum of consecutive naturals, namely, 320543159 + ... + 320543174.

Almost surely, 2^5128690664 is an apocalyptic number.

It is an amenable number.

5128690664 is a deficient number, since it is larger than the sum of its proper divisors (4487604346).

5128690664 is a wasteful number, since it uses less digits than its factorization.

5128690664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 641086339 (or 641086335 counting only the distinct ones).

The product of its (nonzero) digits is 622080, while the sum is 47.

The square root of 5128690664 is about 71614.8773928993. The cubic root of 5128690664 is about 1724.5223814146.

The spelling of 5128690664 in words is "five billion, one hundred twenty-eight million, six hundred ninety thousand, six hundred sixty-four".