66641128704 has 432 divisors, whose sum is σ = 206419799040. Its totient is φ = 21431900160.

The previous prime is 66641128693. The next prime is 66641128727. The reversal of 66641128704 is 40782114666.

It is a tau number, because it is divible by the number of its divisors (432).

It is a self number, because there is not a number n which added to its sum of digits gives 66641128704.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 245908089 + ... + 245908359.

Almost surely, 2^66641128704 is an apocalyptic number.

66641128704 is a gapful number since it is divisible by the number (64) 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 66641128704, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (103209899520).

66641128704 is an abundant number, since it is smaller than the sum of its proper divisors (139778670336).

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

66641128704 is an equidigital number, since it uses as much as digits as its factorization.

66641128704 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 428 (or 402 counting only the distinct ones).

The product of its (nonzero) digits is 387072, while the sum is 45.

The spelling of 66641128704 in words is "sixty-six billion, six hundred forty-one million, one hundred twenty-eight thousand, seven hundred four".