64640518 has 32 divisors (see below), whose sum is σ = 104509440. Its totient is φ = 29928000.

The previous prime is 64640503. The next prime is 64640539. The reversal of 64640518 is 81504646.

64640518 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

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 15 ways as a sum of consecutive naturals, for example, 149763 + ... + 150193.

It is an arithmetic number, because the mean of its divisors is an integer number (3265920).

Almost surely, 2^64640518 is an apocalyptic number.

64640518 is a deficient number, since it is larger than the sum of its proper divisors (39868922).

64640518 is a wasteful number, since it uses less digits than its factorization.

64640518 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 564.

The product of its (nonzero) digits is 23040, while the sum is 34.

The square root of 64640518 is about 8039.9327111612. The cubic root of 64640518 is about 401.3299854456.

The spelling of 64640518 in words is "sixty-four million, six hundred forty thousand, five hundred eighteen".