66788721120 has 384 divisors, whose sum is σ = 240209722368. Its totient is φ = 15440691200.

The previous prime is 66788721101. The next prime is 66788721133. The reversal of 66788721120 is 2112788766.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 66788721120.

It is a congruent number.

It is an unprimeable number.

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 63 ways as a sum of consecutive naturals, for example, 55983244 + ... + 55984436.

It is an arithmetic number, because the mean of its divisors is an integer number (625546152).

Almost surely, 2^66788721120 is an apocalyptic number.

66788721120 is a gapful number since it is divisible by the number (60) 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 66788721120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (120104861184).

66788721120 is an abundant number, since it is smaller than the sum of its proper divisors (173421001248).

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

66788721120 is a wasteful number, since it uses less digits than its factorization.

66788721120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1706 (or 1698 counting only the distinct ones).

The product of its (nonzero) digits is 451584, while the sum is 48.

The spelling of 66788721120 in words is "sixty-six billion, seven hundred eighty-eight million, seven hundred twenty-one thousand, one hundred twenty".