66804856 has 8 divisors (see below), whose sum is σ = 125259120. Its totient is φ = 33402424.

The previous prime is 66804853. The next prime is 66804863. The reversal of 66804856 is 65840866.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66804851) 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 as a sum of consecutive naturals, namely, 4175296 + ... + 4175311.

It is an arithmetic number, because the mean of its divisors is an integer number (15657390).

Almost surely, 2^66804856 is an apocalyptic number.

It is an amenable number.

66804856 is a deficient number, since it is larger than the sum of its proper divisors (58454264).

66804856 is a wasteful number, since it uses less digits than its factorization.

66804856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8350613 (or 8350609 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 43.

The square root of 66804856 is about 8173.4237624144. The cubic root of 66804856 is about 405.7601048280.

The spelling of 66804856 in words is "sixty-six million, eight hundred four thousand, eight hundred fifty-six".