66809307 has 4 divisors (see below), whose sum is σ = 89079080. Its totient is φ = 44539536.

The previous prime is 66809291. The next prime is 66809321. The reversal of 66809307 is 70390866.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 66809307 - 2⁴ = 66809291 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66809357) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11134882 + ... + 11134887.

It is an arithmetic number, because the mean of its divisors is an integer number (22269770).

Almost surely, 2^66809307 is an apocalyptic number.

66809307 is a deficient number, since it is larger than the sum of its proper divisors (22269773).

66809307 is a wasteful number, since it uses less digits than its factorization.

66809307 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22269772.

The product of its (nonzero) digits is 54432, while the sum is 39.

The square root of 66809307 is about 8173.6960427948. The cubic root of 66809307 is about 405.7691161396.

The spelling of 66809307 in words is "sixty-six million, eight hundred nine thousand, three hundred seven".