66305500778 has 16 divisors (see below), whose sum is σ = 109553311296. Its totient is φ = 29846252640.

The previous prime is 66305500777. The next prime is 66305500801. The reversal of 66305500778 is 87700550366.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (66305500771) 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 7 ways as a sum of consecutive naturals, for example, 14628251 + ... + 14632782.

It is an arithmetic number, because the mean of its divisors is an integer number (6847081956).

Almost surely, 2^66305500778 is an apocalyptic number.

66305500778 is a deficient number, since it is larger than the sum of its proper divisors (43247810518).

66305500778 is a wasteful number, since it uses less digits than its factorization.

66305500778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29261149.

The product of its (nonzero) digits is 1058400, while the sum is 47.

The spelling of 66305500778 in words is "sixty-six billion, three hundred five million, five hundred thousand, seven hundred seventy-eight".