64657520 has 40 divisors (see below), whose sum is σ = 150667440. Its totient is φ = 25804800.

The previous prime is 64657519. The next prime is 64657543. The reversal of 64657520 is 2575646.

64657520 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (40).

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 7 ways as a sum of consecutive naturals, for example, 60995 + ... + 62045.

It is an arithmetic number, because the mean of its divisors is an integer number (3766686).

Almost surely, 2^64657520 is an apocalyptic number.

It is an amenable number.

64657520 is an abundant number, since it is smaller than the sum of its proper divisors (86009920).

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

64657520 is a wasteful number, since it uses less digits than its factorization.

64657520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1833 (or 1827 counting only the distinct ones).

The product of its (nonzero) digits is 50400, while the sum is 35.

The square root of 64657520 is about 8040.9899888011. The cubic root of 64657520 is about 401.3651688181.

The spelling of 64657520 in words is "sixty-four million, six hundred fifty-seven thousand, five hundred twenty".