64855585440 has 240 divisors, whose sum is σ = 229707944928. Its totient is φ = 17232735744.

The previous prime is 64855585411. The next prime is 64855585477. The reversal of 64855585440 is 4458555846.

64855585440 is a `hidden beast` number, since 6 + 4 + 8 + 55 + 585 + 4 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 3658839 + ... + 3676521.

Almost surely, 2^64855585440 is an apocalyptic number.

64855585440 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 64855585440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (114853972464).

64855585440 is an abundant number, since it is smaller than the sum of its proper divisors (164852359488).

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

64855585440 is a wasteful number, since it uses less digits than its factorization.

64855585440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17993 (or 17976 counting only the distinct ones).

The product of its (nonzero) digits is 15360000, while the sum is 54.

The spelling of 64855585440 in words is "sixty-four billion, eight hundred fifty-five million, five hundred eighty-five thousand, four hundred forty".