64639520139 has 8 divisors (see below), whose sum is σ = 86188005072. Its totient is φ = 43092024320.

The previous prime is 64639520107. The next prime is 64639520147. The reversal of 64639520139 is 93102593646.

64639520139 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 64639520139 - 2⁵ = 64639520107 is a prime.

It is not an unprimeable number, because it can be changed into a prime (64639520639) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 78294 + ... + 367979.

It is an arithmetic number, because the mean of its divisors is an integer number (10773500634).

Almost surely, 2^64639520139 is an apocalyptic number.

64639520139 is a deficient number, since it is larger than the sum of its proper divisors (21548484933).

64639520139 is a wasteful number, since it uses less digits than its factorization.

64639520139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 494557.

The product of its (nonzero) digits is 1049760, while the sum is 48.

The spelling of 64639520139 in words is "sixty-four billion, six hundred thirty-nine million, five hundred twenty thousand, one hundred thirty-nine".