66806705 has 32 divisors (see below), whose sum is σ = 96092160. Its totient is φ = 43623360.

The previous prime is 66806689. The next prime is 66806711. The reversal of 66806705 is 50760866.

It is not a de Polignac number, because 66806705 - 2⁴ = 66806689 is a prime.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 72236 + ... + 73154.

It is an arithmetic number, because the mean of its divisors is an integer number (3002880).

Almost surely, 2^66806705 is an apocalyptic number.

It is an amenable number.

66806705 is a deficient number, since it is larger than the sum of its proper divisors (29285455).

66806705 is a wasteful number, since it uses less digits than its factorization.

66806705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1029.

The product of its (nonzero) digits is 60480, while the sum is 38.

The square root of 66806705 is about 8173.5368721258. The cubic root of 66806705 is about 405.7638482860.

The spelling of 66806705 in words is "sixty-six million, eight hundred six thousand, seven hundred five".