66805538 has 8 divisors (see below), whose sum is σ = 101415888. Its totient is φ = 33000244.

The previous prime is 66805537. The next prime is 66805559. The reversal of 66805538 is 83550866.

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

It is a junction number, because it is equal to n+sod(n) for n = 66805495 and 66805504.

It is not an unprimeable number, because it can be changed into a prime (66805537) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 201056 + ... + 201387.

It is an arithmetic number, because the mean of its divisors is an integer number (12676986).

Almost surely, 2^66805538 is an apocalyptic number.

66805538 is a deficient number, since it is larger than the sum of its proper divisors (34610350).

66805538 is a wasteful number, since it uses less digits than its factorization.

66805538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 402528.

The product of its (nonzero) digits is 172800, while the sum is 41.

The square root of 66805538 is about 8173.4654828904. The cubic root of 66805538 is about 405.7614856031.

The spelling of 66805538 in words is "sixty-six million, eight hundred five thousand, five hundred thirty-eight".