64939511616 has 224 divisors, whose sum is σ = 203463997440. Its totient is φ = 17885435904.

The previous prime is 64939511509. The next prime is 64939511629. The reversal of 64939511616 is 61611593946.

64939511616 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 (224).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 37688931 + ... + 37690653.

Almost surely, 2^64939511616 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 64939511616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (101731998720).

64939511616 is an abundant number, since it is smaller than the sum of its proper divisors (138524485824).

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

64939511616 is a wasteful number, since it uses less digits than its factorization.

64939511616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2741 (or 2731 counting only the distinct ones).

The product of its digits is 1049760, while the sum is 51.

The spelling of 64939511616 in words is "sixty-four billion, nine hundred thirty-nine million, five hundred eleven thousand, six hundred sixteen".