639476065 has 8 divisors (see below), whose sum is σ = 807759360. Its totient is φ = 484655472.

The previous prime is 639476011. The next prime is 639476081. The reversal of 639476065 is 560674936.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 639476065 - 2²⁷ = 505258337 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3365569 + ... + 3365758.

It is an arithmetic number, because the mean of its divisors is an integer number (100969920).

Almost surely, 2^639476065 is an apocalyptic number.

It is an amenable number.

639476065 is a deficient number, since it is larger than the sum of its proper divisors (168283295).

639476065 is a wasteful number, since it uses less digits than its factorization.

639476065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6731351.

The product of its (nonzero) digits is 816480, while the sum is 46.

The square root of 639476065 is about 25287.8639865055. The cubic root of 639476065 is about 861.5386485325.

Subtracting from 639476065 its reverse (560674936), we obtain a square (78801129 = 8877²).

The spelling of 639476065 in words is "six hundred thirty-nine million, four hundred seventy-six thousand, sixty-five".