66821334740 has 48 divisors (see below), whose sum is σ = 144351177600. Its totient is φ = 25963949952.

The previous prime is 66821334739. The next prime is 66821334791. The reversal of 66821334740 is 4743312866.

It is a junction number, because it is equal to n+sod(n) for n = 66821334691 and 66821334700.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 385121 + ... + 530999.

It is an arithmetic number, because the mean of its divisors is an integer number (3007316200).

Almost surely, 2^66821334740 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 66821334740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (72175588800).

66821334740 is an abundant number, since it is smaller than the sum of its proper divisors (77529842860).

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

66821334740 is a wasteful number, since it uses less digits than its factorization.

66821334740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 146544 (or 146542 counting only the distinct ones).

The product of its (nonzero) digits is 580608, while the sum is 44.

The spelling of 66821334740 in words is "sixty-six billion, eight hundred twenty-one million, three hundred thirty-four thousand, seven hundred forty".