66823556597568 has 168 divisors, whose sum is σ = 192035976664896. Its totient is φ = 22216626432000.

The previous prime is 66823556597561. The next prime is 66823556597569. The reversal of 66823556597568 is 86579565532866.

66823556597568 is a `hidden beast` number, since 6 + 6 + 8 + 2 + 3 + 556 + 5 + 9 + 7 + 56 + 8 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66823556597561) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 444967293 + ... + 445117443.

It is an arithmetic number, because the mean of its divisors is an integer number (1143071289672).

Almost surely, 2^{66823556597568} 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 66823556597568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (96017988332448).

66823556597568 is an abundant number, since it is smaller than the sum of its proper divisors (125212420067328).

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

66823556597568 is a wasteful number, since it uses less digits than its factorization.

66823556597568 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 152173 (or 152160 counting only the distinct ones).

The product of its digits is 19595520000, while the sum is 81.

The spelling of 66823556597568 in words is "sixty-six trillion, eight hundred twenty-three billion, five hundred fifty-six million, five hundred ninety-seven thousand, five hundred sixty-eight".