66821098176 has 896 divisors, whose sum is σ = 249067929600. Its totient is φ = 17139548160.

The previous prime is 66821098147. The next prime is 66821098177. The reversal of 66821098176 is 67189012866.

It is a super-2 number, since 2×66821098176² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (66821098177) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 591337096 + ... + 591337208.

It is an arithmetic number, because the mean of its divisors is an integer number (277977600).

Almost surely, 2^66821098176 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 66821098176, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (124533964800).

66821098176 is an abundant number, since it is smaller than the sum of its proper divisors (182246831424).

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

66821098176 is a wasteful number, since it uses less digits than its factorization.

66821098176 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 274 (or 258 counting only the distinct ones).

The product of its (nonzero) digits is 1741824, while the sum is 54.

The spelling of 66821098176 in words is "sixty-six billion, eight hundred twenty-one million, ninety-eight thousand, one hundred seventy-six".