66633813 has 8 divisors (see below), whose sum is σ = 98716800. Its totient is φ = 44422524.

The previous prime is 66633739. The next prime is 66633857. The reversal of 66633813 is 31833666.

66633813 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 66633813 - 2¹⁰ = 66632789 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 (66633113) 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 7 ways as a sum of consecutive naturals, for example, 1233933 + ... + 1233986.

It is an arithmetic number, because the mean of its divisors is an integer number (12339600).

Almost surely, 2^66633813 is an apocalyptic number.

It is an amenable number.

66633813 is a deficient number, since it is larger than the sum of its proper divisors (32082987).

66633813 is a wasteful number, since it uses less digits than its factorization.

66633813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2467928 (or 2467922 counting only the distinct ones).

The product of its digits is 46656, while the sum is 36.

The square root of 66633813 is about 8162.9536933637. The cubic root of 66633813 is about 405.4135145481.

The spelling of 66633813 in words is "sixty-six million, six hundred thirty-three thousand, eight hundred thirteen".