66774873880 has 128 divisors (see below), whose sum is σ = 177290830080. Its totient is φ = 22314769920.

The previous prime is 66774873871. The next prime is 66774873881. The reversal of 66774873880 is 8837847766.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66774873881) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1272727 + ... + 1324153.

It is an arithmetic number, because the mean of its divisors is an integer number (1385084610).

Almost surely, 2^66774873880 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 66774873880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (88645415040).

66774873880 is an abundant number, since it is smaller than the sum of its proper divisors (110515956200).

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

66774873880 is a wasteful number, since it uses less digits than its factorization.

66774873880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51689 (or 51685 counting only the distinct ones).

The product of its (nonzero) digits is 75866112, while the sum is 64.

The spelling of 66774873880 in words is "sixty-six billion, seven hundred seventy-four million, eight hundred seventy-three thousand, eight hundred eighty".