64721825280 has 960 divisors, whose sum is σ = 270252702720. Its totient is φ = 14539751424.

The previous prime is 64721825279. The next prime is 64721825339. The reversal of 64721825280 is 8252812746.

64721825280 is a `hidden beast` number, since 6 + 47 + 2 + 1 + 82 + 528 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (960).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 387555757 + ... + 387555923.

It is an arithmetic number, because the mean of its divisors is an integer number (281513232).

Almost surely, 2^64721825280 is an apocalyptic number.

64721825280 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 64721825280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (135126351360).

64721825280 is an abundant number, since it is smaller than the sum of its proper divisors (205530877440).

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

64721825280 is an equidigital number, since it uses as much as digits as its factorization.

64721825280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 301 (or 273 counting only the distinct ones).

The product of its (nonzero) digits is 430080, while the sum is 45.

The spelling of 64721825280 in words is "sixty-four billion, seven hundred twenty-one million, eight hundred twenty-five thousand, two hundred eighty".