64561336519680 has 3960 divisors, whose sum is σ = 318095675702640. Its totient is φ = 12376147230720.

The previous prime is 64561336519661. The next prime is 64561336519681. The reversal of 64561336519680 is 8691563316546.

64561336519680 is a `hidden beast` number, since 6 + 4 + 5 + 6 + 1 + 3 + 36 + 519 + 6 + 80 = 666.

64561336519680 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 (3960).

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64561336519681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 359 ways as a sum of consecutive naturals, for example, 37777258666 + ... + 37777260374.

It is an arithmetic number, because the mean of its divisors is an integer number (80327190834).

Almost surely, 2^{64561336519680} is an apocalyptic number.

64561336519680 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 64561336519680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (159047837851320).

64561336519680 is an abundant number, since it is smaller than the sum of its proper divisors (253534339182960).

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

64561336519680 is a wasteful number, since it uses less digits than its factorization.

64561336519680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1797 (or 1750 counting only the distinct ones).

The product of its (nonzero) digits is 83980800, while the sum is 63.

The spelling of 64561336519680 in words is "sixty-four trillion, five hundred sixty-one billion, three hundred thirty-six million, five hundred nineteen thousand, six hundred eighty".