64717520 has 80 divisors (see below), whose sum is σ = 173262720. Its totient is φ = 22021632.

The previous prime is 64717519. The next prime is 64717579. The reversal of 64717520 is 2571746.

64717520 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 (80).

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, 90926 + ... + 91634.

It is an arithmetic number, because the mean of its divisors is an integer number (2165784).

Almost surely, 2^64717520 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 64717520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (86631360).

64717520 is an abundant number, since it is smaller than the sum of its proper divisors (108545200).

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

64717520 is a wasteful number, since it uses less digits than its factorization.

64717520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 892 (or 886 counting only the distinct ones).

The product of its (nonzero) digits is 11760, while the sum is 32.

The square root of 64717520 is about 8044.7200075578. The cubic root of 64717520 is about 401.4892815529.

The spelling of 64717520 in words is "sixty-four million, seven hundred seventeen thousand, five hundred twenty".