666195199 has 2 divisors, whose sum is σ = 666195200. Its totient is φ = 666195198.

The previous prime is 666195191. The next prime is 666195217. The reversal of 666195199 is 991591666.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 666195199 - 2³ = 666195191 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (666195191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333097599 + 333097600.

It is an arithmetic number, because the mean of its divisors is an integer number (333097600).

Almost surely, 2^666195199 is an apocalyptic number.

666195199 is a deficient number, since it is larger than the sum of its proper divisors (1).

666195199 is an equidigital number, since it uses as much as digits as its factorization.

666195199 is an evil number, because the sum of its binary digits is even.

The product of its digits is 787320, while the sum is 52.

The square root of 666195199 is about 25810.7574278633. The cubic root of 666195199 is about 873.3744837003.

The spelling of 666195199 in words is "six hundred sixty-six million, one hundred ninety-five thousand, one hundred ninety-nine".