66066021 has 48 divisors (see below), whose sum is σ = 116188800. Its totient is φ = 35334144.

The previous prime is 66065977. The next prime is 66066043. The reversal of 66066021 is 12066066.

66066021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 66066021 - 2¹⁰ = 66064997 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66066521) 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 47 ways as a sum of consecutive naturals, for example, 115825 + ... + 116393.

It is an arithmetic number, because the mean of its divisors is an integer number (2420600).

Almost surely, 2^66066021 is an apocalyptic number.

It is an amenable number.

66066021 is a deficient number, since it is larger than the sum of its proper divisors (50122779).

66066021 is a wasteful number, since it uses less digits than its factorization.

66066021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 698 (or 695 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 66066021 is about 8128.1007006557. The cubic root of 66066021 is about 404.2587080183.

The spelling of 66066021 in words is "sixty-six million, sixty-six thousand, twenty-one".