64686433680 has 320 divisors, whose sum is σ = 245303942400. Its totient is φ = 15537070080.

The previous prime is 64686433673. The next prime is 64686433703. The reversal of 64686433680 is 8633468646.

64686433680 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 (54).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2577352 + ... + 2602328.

It is an arithmetic number, because the mean of its divisors is an integer number (766574820).

Almost surely, 2^64686433680 is an apocalyptic number.

64686433680 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 64686433680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (122651971200).

64686433680 is an abundant number, since it is smaller than the sum of its proper divisors (180617508720).

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

64686433680 is a wasteful number, since it uses less digits than its factorization.

64686433680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25119 (or 25107 counting only the distinct ones).

The product of its (nonzero) digits is 11943936, while the sum is 54.

The spelling of 64686433680 in words is "sixty-four billion, six hundred eighty-six million, four hundred thirty-three thousand, six hundred eighty".