66076709 has 4 divisors (see below), whose sum is σ = 67862604. Its totient is φ = 64290816.

The previous prime is 66076687. The next prime is 66076711. The reversal of 66076709 is 90767066.

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

It can be written as a sum of positive squares in 2 ways, for example, as 63760225 + 2316484 = 7985^2 + 1522^2 .

It is a cyclic number.

It is not a de Polignac number, because 66076709 - 2⁸ = 66076453 is a prime.

It is a super-2 number, since 2×66076709² = 8732262944541362, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66070709) 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, 892892 + ... + 892965.

It is an arithmetic number, because the mean of its divisors is an integer number (16965651).

Almost surely, 2^66076709 is an apocalyptic number.

It is an amenable number.

66076709 is a deficient number, since it is larger than the sum of its proper divisors (1785895).

66076709 is a wasteful number, since it uses less digits than its factorization.

66076709 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1785894.

The product of its (nonzero) digits is 95256, while the sum is 41.

The square root of 66076709 is about 8128.7581462361. The cubic root of 66076709 is about 404.2805068392.

The spelling of 66076709 in words is "sixty-six million, seventy-six thousand, seven hundred nine".