66818081 has 8 divisors (see below), whose sum is σ = 73000704. Its totient is φ = 60653520.

The previous prime is 66818053. The next prime is 66818093. The reversal of 66818081 is 18081866.

66818081 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66818081 - 2¹⁰ = 66817057 is a prime.

It is a super-2 number, since 2×66818081² = 8929311897045122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66818021) 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, 3920 + ... + 12206.

It is an arithmetic number, because the mean of its divisors is an integer number (9125088).

Almost surely, 2^66818081 is an apocalyptic number.

It is an amenable number.

66818081 is a deficient number, since it is larger than the sum of its proper divisors (6182623).

66818081 is a wasteful number, since it uses less digits than its factorization.

66818081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9031.

The product of its (nonzero) digits is 18432, while the sum is 38.

The square root of 66818081 is about 8174.2327468699. The cubic root of 66818081 is about 405.7868784472.

The spelling of 66818081 in words is "sixty-six million, eight hundred eighteen thousand, eighty-one".