66065978 has 24 divisors (see below), whose sum is σ = 114852384. Its totient is φ = 28260800.

The previous prime is 66065977. The next prime is 66066043. The reversal of 66065978 is 87956066.

66065978 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (66065977) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1163 + ... + 11553.

It is an arithmetic number, because the mean of its divisors is an integer number (4785516).

Almost surely, 2^66065978 is an apocalyptic number.

66065978 is a deficient number, since it is larger than the sum of its proper divisors (48786406).

66065978 is a wasteful number, since it uses less digits than its factorization.

66065978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10438 (or 10421 counting only the distinct ones).

The product of its (nonzero) digits is 544320, while the sum is 47.

The square root of 66065978 is about 8128.0980555109. The cubic root of 66065978 is about 404.2586203124.

The spelling of 66065978 in words is "sixty-six million, sixty-five thousand, nine hundred seventy-eight".