64446512520 has 128 divisors (see below), whose sum is σ = 209084198400. Its totient is φ = 15797289984.

The previous prime is 64446512503. The next prime is 64446512617. The reversal of 64446512520 is 2521564446.

64446512520 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 286414 + ... + 459266.

It is an arithmetic number, because the mean of its divisors is an integer number (1633470300).

Almost surely, 2^64446512520 is an apocalyptic number.

64446512520 is a gapful number since it is divisible by the number (60) 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 64446512520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (104542099200).

64446512520 is an abundant number, since it is smaller than the sum of its proper divisors (144637685880).

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

64446512520 is a wasteful number, since it uses less digits than its factorization.

64446512520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173119 (or 173115 counting only the distinct ones).

The product of its (nonzero) digits is 230400, while the sum is 39.

The spelling of 64446512520 in words is "sixty-four billion, four hundred forty-six million, five hundred twelve thousand, five hundred twenty".