639463915 has 16 divisors (see below), whose sum is σ = 783137376. Its totient is φ = 501120000.

The previous prime is 639463907. The next prime is 639463919. The reversal of 639463915 is 519364936.

It is not a de Polignac number, because 639463915 - 2³ = 639463907 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (639463919) 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 in 15 ways as a sum of consecutive naturals, for example, 72379 + ... + 80731.

It is an arithmetic number, because the mean of its divisors is an integer number (48946086).

Almost surely, 2^639463915 is an apocalyptic number.

639463915 is a deficient number, since it is larger than the sum of its proper divisors (143673461).

639463915 is a wasteful number, since it uses less digits than its factorization.

639463915 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8670.

The product of its digits is 524880, while the sum is 46.

The square root of 639463915 is about 25287.6237515509. The cubic root of 639463915 is about 861.5331921068.

The spelling of 639463915 in words is "six hundred thirty-nine million, four hundred sixty-three thousand, nine hundred fifteen".