63644894720 has 160 divisors (see below), whose sum is σ = 171843572736. Its totient is φ = 22396723200.

The previous prime is 63644894713. The next prime is 63644894723. The reversal of 63644894720 is 2749844636.

It is a tau number, because it is divible by the number of its divisors (160).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63644894723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 836507 + ... + 909413.

Almost surely, 2^63644894720 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 63644894720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (85921786368).

63644894720 is an abundant number, since it is smaller than the sum of its proper divisors (108198678016).

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

63644894720 is a wasteful number, since it uses less digits than its factorization.

63644894720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72972 (or 72956 counting only the distinct ones).

The product of its (nonzero) digits is 6967296, while the sum is 53.

The spelling of 63644894720 in words is "sixty-three billion, six hundred forty-four million, eight hundred ninety-four thousand, seven hundred twenty".