64515728688 has 160 divisors (see below), whose sum is σ = 178976044800. Its totient is φ = 19953819648.

The previous prime is 64515728681. The next prime is 64515728689. The reversal of 64515728688 is 88682751546.

It is not an unprimeable number, because it can be changed into a prime (64515728681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 50050348 + ... + 50051636.

It is an arithmetic number, because the mean of its divisors is an integer number (1118600280).

Almost surely, 2^64515728688 is an apocalyptic number.

64515728688 is a gapful number since it is divisible by the number (68) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 64515728688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (89488022400).

64515728688 is an abundant number, since it is smaller than the sum of its proper divisors (114460316112).

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

64515728688 is a wasteful number, since it uses less digits than its factorization.

64515728688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2139 (or 2133 counting only the distinct ones).

The product of its digits is 25804800, while the sum is 60.

The spelling of 64515728688 in words is "sixty-four billion, five hundred fifteen million, seven hundred twenty-eight thousand, six hundred eighty-eight".