66721116021016 has 32 divisors (see below), whose sum is σ = 132461472167280. Its totient is φ = 31398069606400.

The previous prime is 66721116020971. The next prime is 66721116021031. The reversal of 66721116021016 is 61012061112766.

66721116021016 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 66721116021016.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 55366656 + ... + 56558896.

Almost surely, 2^{66721116021016} is an apocalyptic number.

It is an amenable number.

66721116021016 is a deficient number, since it is larger than the sum of its proper divisors (65740356146264).

66721116021016 is a wasteful number, since it uses less digits than its factorization.

66721116021016 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1603755 (or 1603751 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 40.

The spelling of 66721116021016 in words is "sixty-six trillion, seven hundred twenty-one billion, one hundred sixteen million, twenty-one thousand, sixteen".