66196209 has 16 divisors (see below), whose sum is σ = 93193280. Its totient is φ = 41795136.

The previous prime is 66196187. The next prime is 66196213. The reversal of 66196209 is 90269166.

It is not a de Polignac number, because 66196209 - 2²⁰ = 65147633 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66196279) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18969 + ... + 22185.

It is an arithmetic number, because the mean of its divisors is an integer number (5824580).

Almost surely, 2^66196209 is an apocalyptic number.

It is an amenable number.

66196209 is a deficient number, since it is larger than the sum of its proper divisors (26997071).

66196209 is an equidigital number, since it uses as much as digits as its factorization.

66196209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3277 (or 3239 counting only the distinct ones).

The product of its (nonzero) digits is 34992, while the sum is 39.

The square root of 66196209 is about 8136.1052721803. The cubic root of 66196209 is about 404.5240743870.

The spelling of 66196209 in words is "sixty-six million, one hundred ninety-six thousand, two hundred nine".