64639888 has 40 divisors (see below), whose sum is σ = 129726072. Its totient is φ = 31177728.

The previous prime is 64639873. The next prime is 64639901. The reversal of 64639888 is 88893646.

64639888 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 24088464 + 40551424 = 4908^2 + 6368^2 .

It is a Smith number, since the sum of its digits (52) coincides with the sum of the digits of its prime factors.

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, 80706 + ... + 81502.

Almost surely, 2^64639888 is an apocalyptic number.

It is an amenable number.

64639888 is an abundant number, since it is smaller than the sum of its proper divisors (65086184).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

64639888 is a wasteful number, since it uses less digits than its factorization.

64639888 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 979 (or 973 counting only the distinct ones).

The product of its digits is 1990656, while the sum is 52.

The square root of 64639888 is about 8039.8935316334. The cubic root of 64639888 is about 401.3286816261.

The spelling of 64639888 in words is "sixty-four million, six hundred thirty-nine thousand, eight hundred eighty-eight".