66616807 has 4 divisors (see below), whose sum is σ = 67529440. Its totient is φ = 65704176.

The previous prime is 66616721. The next prime is 66616843. The reversal of 66616807 is 70861666.

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 66616807 - 2¹¹ = 66614759 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66616807.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66610807) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 456207 + ... + 456352.

It is an arithmetic number, because the mean of its divisors is an integer number (16882360).

Almost surely, 2^66616807 is an apocalyptic number.

66616807 is a deficient number, since it is larger than the sum of its proper divisors (912633).

66616807 is an equidigital number, since it uses as much as digits as its factorization.

66616807 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 912632.

The product of its (nonzero) digits is 72576, while the sum is 40.

The square root of 66616807 is about 8161.9119696306. The cubic root of 66616807 is about 405.3790223059.

The spelling of 66616807 in words is "sixty-six million, six hundred sixteen thousand, eight hundred seven".