66009707 has 4 divisors (see below), whose sum is σ = 66391440. Its totient is φ = 65627976.

The previous prime is 66009703. The next prime is 66009709. The reversal of 66009707 is 70790066.

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

It is a cyclic number.

It is not a de Polignac number, because 66009707 - 2² = 66009703 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66009703) 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, 190607 + ... + 190952.

It is an arithmetic number, because the mean of its divisors is an integer number (16597860).

Almost surely, 2^66009707 is an apocalyptic number.

66009707 is a deficient number, since it is larger than the sum of its proper divisors (381733).

66009707 is a wasteful number, since it uses less digits than its factorization.

66009707 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 381732.

The product of its (nonzero) digits is 15876, while the sum is 35.

The square root of 66009707 is about 8124.6358072224. The cubic root of 66009707 is about 404.1438133722.

The spelling of 66009707 in words is "sixty-six million, nine thousand, seven hundred seven".