65998550016 has 396 divisors, whose sum is σ = 234750213828. Its totient is φ = 17745444864.

The previous prime is 65998550011. The next prime is 65998550099. The reversal of 65998550016 is 61005589956.

65998550016 is a `hidden beast` number, since 6 + 59 + 9 + 85 + 500 + 1 + 6 = 666.

65998550016 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 49177497600 + 16821052416 = 221760^2 + 129696^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65998550011) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 7672630 + ... + 7681226.

Almost surely, 2^65998550016 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 65998550016, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (117375106914).

65998550016 is an abundant number, since it is smaller than the sum of its proper divisors (168751663812).

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

65998550016 is a wasteful number, since it uses less digits than its factorization.

65998550016 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8654 (or 8626 counting only the distinct ones).

The product of its (nonzero) digits is 2916000, while the sum is 54.

The spelling of 65998550016 in words is "sixty-five billion, nine hundred ninety-eight million, five hundred fifty thousand, sixteen".