66690583 has 4 divisors (see below), whose sum is σ = 67494168. Its totient is φ = 65887000.

The previous prime is 66690553. The next prime is 66690587. The reversal of 66690583 is 38509666.

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 66690583 - 2²⁵ = 33136151 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66690587) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 401668 + ... + 401833.

It is an arithmetic number, because the mean of its divisors is an integer number (16873542).

Almost surely, 2^66690583 is an apocalyptic number.

66690583 is a deficient number, since it is larger than the sum of its proper divisors (803585).

66690583 is an equidigital number, since it uses as much as digits as its factorization.

66690583 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 803584.

The product of its (nonzero) digits is 233280, while the sum is 43.

The square root of 66690583 is about 8166.4302482786. The cubic root of 66690583 is about 405.5286152312.

The spelling of 66690583 in words is "sixty-six million, six hundred ninety thousand, five hundred eighty-three".