66551410640000 has 640 divisors, whose sum is σ = 196065185057280. Its totient is φ = 22175354880000.

The previous prime is 66551410639997. The next prime is 66551410640047. The reversal of 66551410640000 is 4601415566.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (640).

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 1567258769 + ... + 1567301231.

It is an arithmetic number, because the mean of its divisors is an integer number (306351851652).

Almost surely, 2^{66551410640000} 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 66551410640000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98032592528640).

66551410640000 is an abundant number, since it is smaller than the sum of its proper divisors (129513774417280).

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

66551410640000 is a wasteful number, since it uses less digits than its factorization.

66551410640000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42658 (or 42631 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 38.

The spelling of 66551410640000 in words is "sixty-six trillion, five hundred fifty-one billion, four hundred ten million, six hundred forty thousand".